Written submissions: 9, 30 October; 6 November 2024

Torts - Negligence - Pure economic loss - Particular cases of economic loss - Defective buildings - Damages - Assessment of damages in tort - Property loss - Heads of loss - Economic loss generally - Renovations of residence including addition of second floor level - Original footings inadequate to carry additional load - Resultant subsidence and cracking - Defendant negligent in failing to adequately assess existing footings in prevailing soil conditions and to advise of the need for underpinning - Finding that cause of damage was insufficiency of existing footings.

Damages - Assessment of damages in tort - Property loss - Heads of loss - Economic loss generally - Renovations of residence including addition of second floor level - Original footings inadequate to carry additional load - Resultant subsidence and cracking - Internal defects to the structure - Loss suffered is accordingly pure economic loss - Damages to be reduced by amount plaintiff would have spent on underpinning had the problem been identified at the time of the renovations.

Woolcock Street Investments Pty Ltd v CDG Pty Ltd [2004] HCA 16, 216 CLR 515 followed.

Auburn Municipal Council v ARC Engineering Pty Ltd [1973] 1 NSWLR 513, Bevan Investments Limited v Blackhall and Struthers (No 2) [1978] 2 NZLR 97, De Pasquale Bros Pty Ltd v Cavanagh Biggs & Partners Pty Ltd [1999] QSC 171, [2000] 2 Qd R 461; applied.

Damages - Assessment of damages in tort - Property loss - Particular interests - Interests in land or buildings - Generally - Renovations of residence including addition of significant second floor level - Measure of damages agreed to be costs of restoration - Where significant differences in scope and costs of methods of restoration proposed by each party - Method adopted has to be reasonable - Defendant's proposal would leave plaintiff with a doubtful remedy and a real risk of further and increasing damage.

Bellgrove v Eldridge [1954] HCA 36; (1954) 90 CLR 613 followed.

Kirkby v Coote [2006] QCA 61, Metricon Homes Pty Ltd v Softle [2016] VSCA 60, 49 VR 746; applied.

Judgment Number: [2025] TASSC 41

CAMPBELL SYDNEY McDOUGALL v JSA CONSULTING ENGINEERS PTY LTD

1. This is an action for damages. It is about a house at Woodbridge, bought in 2010 by Campbell McDougall and his wife Linda McDougall, into which they moved in February 2011. The house was built in 1983. Once renovated, it was intended to be a "retirement home" for the couple. The renovations involved alterations and extensions to the existing lower-level footprint but, more significantly, construction of an extended upper level containing a study, sunroom, living space, bedroom and separate bathroom. At the time of purchase, the house had an upper level but of much lesser dimensions than the one proposed, and one which could properly be described as a loft or attic. The new upper storey brought a substantial increase in the floor area to that which existed before.
2. The house is, very generally, a rectangular shape and is orientated on a northwest/southeast line but for convenience was mostly referred to in the trial as being on a north/south line. The renovations started in March 2013 and were completed in November of that year. In February 2014, a crack appeared in the brickwork near the front door. Since then, damage by cracking has progressively spread and worsened, inside and out. This cracking is at various points in the house, mainly on the lower level and particularly at the southern end. There is common ground that movement in at least part of the house has occurred through its existing footings, but none in relation to whether those footings were adequate for the purposes of the renovations nor, it seems whether movement is continuing.
3. Sadly, Mrs McDougall passed away in April 2024. She was a plaintiff in these proceedings, but her name has been removed from the action's title. As Mrs McDougall was involved in relevant events, there are times in these reasons where I will, as appropriate to the context, refer to "the plaintiffs" or to her by name. References to "the plaintiff" are to Mr McDougall.
4. The original plans for the renovations were drawn by an architect in November 2012. The architect contacted Matthew Horsham who was a principal in the business known as JSA Consulting Engineers conducted by the defendant company. As a structural engineer, Mr Horsham was engaged to provide engineering design services for the renovation. He was to assist the architect in preparing "a set of working drawings" as he put it in evidence. Ultimately, the architect did not carry on with the project and Mr Horsham arranged for a building designer to complete the plans to building permit standard.
5. Parts of the quotation which was provided to the plaintiffs by the defendant refer to "Consultation on engineering design during the development of the building application documentation" and "Design footings, timber and steel framing, bracing, lintels and roof modifications." It is common ground that Mr Horsham provided engineering input and approved, from his perspective, the plans submitted to the council for a building permit in February 2013. He had carried out at least one site inspection by that time, and thereafter a few more before completion and the lodgement of the relevant documents with the council.
6. Primarily, it is the suitability of the footings of the original building to the extent shown by the designer's drawings and as revealed by such inspections as were carried out by Mr Horsham which is at the heart of the dispute. Only two additional strip footings which related to a dining room on the eastern side and kitchen on the northern end were to be added in the renovation process. Some pad footings were added which related to extensions to a deck. The plaintiff's case is that the footings for the whole of the renovated house were inadequate to support the new upper level. In short summary, he alleges the defendant is liable for Mr Horsham's negligence in failing to adequately investigate the dimensions of the existing footings and failing to carry out a sufficient investigation of the whole of the site.
7. The defendant's position is that there was no breach of duty in that Mr. Horsham exercised the care and skill required of him in the circumstances. Further, in essence, the defendant says the movement is caused by the presence of a tree which was removed in 2015, and by excessive moisture levels in the soil at the southern end with varying causes. More broadly, the defendant's expert evidence is that irrespective of the added level and associated renovations, the house would have subsided and suffered similar damage in any event. It follows that negligence, including the scope of the duty of care and any breach of that duty, and causation are in dispute. A further issue is the best method of rectification. There is expert evidence on both sides of the arguments. The damage by subsidence and cracking is very substantial with damages claimed in the order of $1.5 million. In addition to the evidence of quite a few experts and a plethora of reports, plans, and photographs, I have had the benefit of a view of the house and surrounds.

1. Russell Kingston, a forensic structural engineer called by the defendant, takes the view that in support of the notion that the house would have suffered the same damage in any event given the prevailing ground conditions, there is evidence of movement in the house causing cracking before the renovations began. Both John Bryant, the owner who sold the property to the plaintiffs, and Eric Bound, a builder who provided to the plaintiffs a building inspection report, gave evidence. Mr Bound's report is dated 6 November 2010. It contains notes as to each room, other areas of the house and the exterior. Among other things, Mr Bound noted minor cracking to a cornice above cupboards in the kitchen, minor cracking to the walls on the landing and rumpus room and minor cracking to some external brickwork.
2. In his evidence, Mr Bound was shown photographs of cracking in two internal areas more at the northern end of the house and asked whether the cracking shown was the sort he would describe as minor such as was seen at the time of his inspection. He said this was definitely not the case. He explained minor cracking would be up to a millimetre and would usually be at sheet joints whether they be on the one plane or in a corner. What is shown in one photograph is actually ripping apart of the plaster sheet as opposed to a joint cracking. He said, "That simply indicates an amazing amount of movement for that to open".
3. Mr Bound inspected the house on 21 June 2024 which was the first time he had been there since his report in November 2011. He walked around the whole house. He said he saw a significant amount of cracking and tearing of plaster work. When asked whether what he saw as comparable to what he saw in November 2011 he said that it was a totally different scenario. To illustrate, he said he questioned himself as to whether it was really the same house. The difference was so pronounced he was shocked.
4. John Bryant bought the house in 1991. Having spent some 44 years in the building industry as a builder and architectural designer, he retired in 2011. The plaintiffs bought the property from him. In 2004 he designed and built himself an extension of the northern end of the house. That was constructed on a concrete slab. He said that during the time he owned and occupied the house, there was no evidence that it had suffered or was suffering structural damage of some kind. He saw no damage to plaster work or any specific signs of movement in the house. As to the outside of the building, he did not notice any signs of movement, cracking or breaking in the brick work. He thought that the brick work in the house was of very good quality.
5. He inspected the house when he purchased it and took note of the brickwork. He thought it was a very well-built work: "I was most satisfied that the brick work was sound as was the rest of the house." As to the mortar he said that it was fine and explained that there may be variations in colour and texture of mortar which can depend on a number of factors. There was no need to repoint any of the brick work during his occupancy, nor carry out any remedial work to any part of the building.
6. In cross-examination Mr Bryant was taken to some much more recent photographs of various cracks in the house. Without exception he said there were no such cracks when he lived there, nor did he have to repair any. Mr Bryant was then taken to some specific aspects. Some of the matters raised came from the Bound report while others came from the report of Russell Kingston, a forensic structural engineer called by the defendant. The first thing was mesh in the brickwork at around the south-eastern corner. Mr Bryant said that he did not put it there and would not have known if it was there because the brick work was intact. (This mesh was later explained by Mr McDougall who said that he put it there to stop vermin getting in.) As to photographs showing small sections of slightly different coloured mortar from surrounding parts, Mr Bryant said that he was not responsible. Next, he said that he was not aware of what is now an internal crack from the area of the door from the sunroom to the veranda and had not repaired any crack.
7. In relation to some cracking to the cornice above the kitchen cupboards, he said that it would surprise him if it were present, as he had put the kitchen in, but he was not aware of it. Nor was he aware of the door to the veranda catching on the door sill as it was opened. He agreed that it was possible that there were "twisting" wardrobe doors. He said a 16 mm gap between the wall and the window architrave in the downstairs bathroom was remedied by replacing a couple of "missing" wind moulds. He said he regarded the Bound report as being about fairly minor issues, and he did as much as he could to satisfy the points. The only external cracking he saw was at each side of the front door where the bricks were vertically laid, and any cracking would have been minor and in the mortar, he was able to identify that cracking in a more recent photograph.
8. Mr McDougall said that when he inspected the property, he did not see anything that led him to think that it had undergone substantial repairs of any kind at some stage. He saw no problems with the brickwork, or any internal damage apart from what was noted by Mr Bound. He saw no signs of movement or subsidence in or of the building. He said that between when they moved in and the start of the renovations, they did not carry out any alterations to the exterior of the building; in particular, the brick work. He did not notice any signs of damage deterioration or failure in any of the exterior brick work, either the bricks or the mortar. He was taken through more recent photographs and confirmed that there was nothing of that type evident when they moved in.
9. In cross-examination, Mr McDougall agreed that when they moved into the house, he was satisfied that most of the issues identified by Mr Bound had been resolved. He was not challenged about his observations of the building before the renovations were carried out. Peter Holmes, a structural engineer called by the plaintiff, said the Bound report mentioned minor cosmetic issues that needed to be addressed. He said he saw nothing in it to raise any concern about building movement; "I am seeing quite the opposite; [the] building is in need of some TLC, some maintenance."
10. Mr Horsham gave evidence. He said that on 24 October 2012 he went to the property with the architect, Craig Meredith, and met the plaintiffs. He carried out an inspection of the property, principally to look at the health of the house. He understood that the house was about 25 years old, and he was looking for tell-tale signs which can include cracks in ceilings, uneven floors and that type of thing. He found the inside of the dwelling to be in very good condition. He said he had "a pretty good eye at spotting stress in houses." That was principally what he was looking for. He said it is typically shown up in the ceilings of most rooms with cracks in the plaster, and he could not spot anything; it was in very good condition.
11. One of his concerns was with the weight of the building and what was carrying the load. Because of that he was particularly interested to look for whether the building had articulation in the masonry, which is built into allow a building to move as foundations move, and brick is brittle. The articulation is a 10 mm gap which effectively acts as a flexibile joint. He did not find articulation. He was also looking for telltale signs of stress in the building, adding that it "very, very hard to hide stress in masonry because ... it is very brittle, and so the slightest of movements - you will see stress develop in one way or another". He inspected the entire perimeter of the building and took a series of photographs. He described a high level of scrutiny to the brick wall work in order to detect movement and said apart from some unusual discolouring on some brick, "the house was in remarkably good condition for its age."
12. The defendant's expert, Mr Kingston, gave evidence of an inspection of the property over two days in April 2024. A lengthy written report constituted much of his evidence-in -chief. Notwithstanding what Mr Horsham said he saw in 2012, Mr Kingston says his reported measurements and observations show settlement of the building at the southern end before completion of the renovations, and also "previous repairs". As to the suggested settlement before completion, in the order in which they appear in the report, Mr Kingston notes the following.

(a) A "built-in horizontal misalignment" between the top of the gallery west wall cupboards[1] and the ceiling, the distances being 78 mm at the northern end and 110 mm at the southern end.

(b) Horizontal misalignment of the downstairs bathroom/bedroom doorway (bathroom side) where the top of the architrave to the cornice on the western side is lower by 8 mm than the other side, said to be "consistent with the floor having relative settlement towards the west and a new horizontal ceiling having been installed.";

(c) Compared to the upper floor levels, the lower floor levels generally have a greater fall to the south, starting approximately in the midline of the building, with the lower floor levels falling by 60 mm compared to 40 mm for the upper floor levels.

1. As to evidence of previous repairs, again in the order in which they appear in the report, Mr Kingston notes the following.

(a) The reopening of a previous repair above the window in the eastern wall of the lower-level bathroom. Photographs show a crack running at an angle from the point near the right corner of the window to the cornice.

(b) "Mesh within re-opening of previous crack repairs." This is identified in two separate areas of the laundry/store area at the southern end of the building, and in the lightwell, also at the southern end. Photographs show a form of white or light-coloured mesh behind and in cracks in plasterboard.

(c) Areas of lighter and darker mortar in the brickwork at the southern end of the house, the properties of which indicate the lighter coloured mortar is newer "and may be associated with previous repairs." In light of what Mr Kingston says in an earlier part of the report, the reference to the southern end includes a reference to the "Store eastern wall." In that part of the report, he says the lighter mortar is "most likely a previous repair." [My emphasis]

(d) A "previous mortar repair" in the north-eastern corner brickwork of the downstairs bedroom on south-eastern side of the building; "[T]he owner was not aware of this crack having been repaired since his purchase, therefore it has been pre-existing to 2010."

(e) The extent of internal distress within the south end of the house is not consistent with the extent of brickwork distress, "suggesting that previous internal repairs may have been carried out."

1. The plaintiff objected to the admissibility of this "previous repair" evidence. The grounds included relevance and a failure to satisfy the requirements of s 79(1) of the Evidence Act 2000.[2] After submissions were made, it was agreed the evidence be taken provisionally. The evidence referred to in pars [19](a), (b) and (e), can be quickly dealt with. The plaintiff did not object to Mr Kingston's expertise as a structural engineer, specialising in forensic work. The relevant parts of the report outline what he saw with cross-references to photographs he took at the time of his inspection. I am satisfied that his opinions in relation to previous repairs, are wholly or substantially based on his specialised knowledge, as that requirement is explained in Dasreef Limited v Hawchar [2011] HCA 21, 243 CLR 588 and Honeysett v The Queen [2014] HCA 29, 253 CLR 122. Parts of the report that relate to the matters referred to in pars 19(a), (b) and (e) are arguably quite sparse in terms of reasoning sufficient to show that the opinion was properly based, but greater clarity emerged in oral evidence. Those expressions of opinion will be admitted. Weight is a separate consideration.
2. As to pars [19](c) and (d), the grounds of objection to the evidence about the lighter brick mortar colour and the likelihood of repairs include relevance, as well as the requirement in the second limb of s 79(1). During his inspection, Mr Kingston was able to observe and photograph differences in mortar colour in three small areas of the southern end of the building. The photographs speak for themselves in any event. He had samples taken of mortar from cracks in some places, as well as drill dust samples. It is his opinion that the differences between samples evidence previous repairs is the subject of the dispute.
3. The argument arises because Mr Kingston's opinion that the lighter mortar colour is evidence of previous brickwork repairs is based on the testing of the mortar samples, carried out by an independent organisation, CMET Technology Pty Ltd, Corrosion Materials & Testing Consultants. The CMET report is attached to Mr Kingston's report, but it is separately in evidence by agreement which means that resort does not need to be had to s 60 of the Evidence Act as to the facts or data contained in it. The suggested issues relate to the terms of the CMET report and Mr Kingston's adoption or interpretation of it.
4. Mortar samples were taken from stepped cracks and drilled holes from and in two separate areas: the downstairs laundry west wall and the downstairs bathroom eastern wall. These became samples A and B respectively, with B described by CMET as "light coloured." Samples of dark and lighter mortar, C and D respectively, were taken from an area of the eastern wall of the store where there is presently no cracking. CMET determined that crack samples A and B were of a similar age, and concluded they had been open for a significant period, estimated to be in the range of five to ten years. It was possible sample B was a different mortar to A. CMET's analysis as to mortar age indicated the lighter coloured mortar in D was a relatively newer mortar than in C, "possibly used to repair cracks in the brickwork." Further, the mortar in B is similar to that in D, and that in A is similar to that in C.
5. From this, Mr Kingston has concluded that the lighter mortar in D from the Store eastern wall is most likely a previous repair. Although not stated by Mr Kingston, the obvious inference from the CMET results is that, as the properties of sample B are similar to those of D, the crack in the bathroom eastern wall had previously appeared but had been repaired and had since reopened.
6. Mr Kingston also stated that lighter coloured mortar in an area of the north-eastern corner of a downstairs bedroom is evidence of a previous repair. No explanation is offered and there is no reference to the CMET results. It may be he has adopted the results for other areas and applied it to this area. The evidence is objected to, but for reasons which will shortly appear, other evidence satisfies me that there was a repair, but it was one necessitated by the renovation works.
7. The objections are essentially to Mr Kingston's evidence, not so much the CMET report. Given that the report is in evidence, the stated facts and opinions are available and can be assessed subject to other evidence. That the CMET report puts previous repairs as possibilities does not affect admissibility: Langmaid v Dobsons Vegetable Machinery Pty Ltd [2014] TASSC 6, 24 Tas R 18 at [24] and the cases cited. The issue is one of weight. To the extent that Mr Kingston advances the opinions as to previous repairs as his own, they appear to be based on the CMET report, and in strict terms, his evidence would be inadmissible as not complying with either limb of s 79(1) of the Evidence Act. To the extent that he has adopted, advanced and exaggerated CMET conclusions, as he has done in relation to the Store eastern wall, the evidence is inadmissible.
8. In argument, Mr Groves for the defendant suggested that all Mr Kingston was offering was that repairs of some description might have been, or had been, made with the reason "to obscure to be identified". It was suggested that if there was work by which original mortar was replaced by newer mortar, that was a proper use of the word "repair". This is a little odd because Mr Kingston's opinion about the cause of subsidence includes reference to the probability of distress having occurred before the plaintiff's purchase in 2010, "with previous repairs having been made" before then. In closing, the defendant submitted that Mr Kingston's opinion about the primary cause of the structural distress - the presence of water in clay soils - was not reliant on the issue of previous repairs but was bolstered by it. It is quite clear to me that the subject evidence was being offered to suggest repairs to cracking caused by movement in the building before the renovations.
9. The plaintiff also argues that the evidence about the age of the stepped cracks is irrelevant because of the stated range of five to ten years which only takes things back to April 2014, some six months after the completion of the renovations. I am not persuaded that there is such a bright line of delineation that would compel the view that the evidence is irrelevant. It is really a question of weight.
10. As to the effect of the evidence itself, I have just mentioned the ultimate context of these matters; that is, the defendant's advanced primary cause of the structural distress is not reliant on the issue of previous repairs but is bolstered by it. Mr Kingston was cross-examined about several of the items. Many of his answers, or his manner of answering, were reflective of his evidence in cross-examination generally, and cause me to have reservations about the cogency of his views. To my mind, Mr Kingston had great difficulty in responding directly, or in any meaningful responsive way, to many questions and was often reluctant to make concessions about obvious points. I will need to again refer to this later.
11. I turn to the par [18](a) matter. The evidence of Mr McDougall about the gallery cupboards is that they are in two sections, one a little longer than the other, and which has been stepped further out. That is because there was a new wall put in behind that section, whereas the shorter cupboard section has the old wall behind it. That shorter cupboard section is to the south. Photographs show that the section measured by Mr Kingston in the longer cupboard. Mr McDougall said that not long before the trial commenced, he measured the other section in the same way Mr Kingston had the longer part - from each end of the relevant section to the ceiling - and could find no discrepancy at all. His photographs show the floor level behind each cupboard section as being generally the same.
12. Other measurements taken by Mr Kingston in this area have some relevance. In the renovations a new roof ridge beam was installed extending to a point approximately above the southern end of the cupboard measured by Mr McDougall. Mr Kingston assumed that it had been installed horizontally, and his measurements show a slight elevation of the south of 2 mm. If there was a previously sloping floor and a horizontal underside of the ceiling, it would explain the horizontal misalignment. However, the original ridge beam to the southern end of the house drops to 16 mm at its southern end point. Mr Kingston's measurements show a drop of 12 mm in the upper floor level from a point about halfway along the total cupboard storage area to its end, with then a further drop to 40 mm at the end of the house. That seems to be evidenced by cracking between the southern end of the cupboard and the adjacent wall.
13. Mr Kingston said that he would not disagree with the proposition that some portion of his measured drop of 16 mm would have occurred since the renovations. In my assessment, the fall of 12 mm in floor level does not correlate with the approximate 30 mm cupboard to ceiling differential, and Mr McDougall's unchallenged measurements of the southern cupboard section remain unexplained. Mr Holmes's view is that the probable cause of the differential is that the wall at that point is not parallel with the ridge beam, the possibility of which Mr Kingston conceded. The general question of different floor levels in this area - par [18](c) - was largely visited in the exchange about the gallery cupboards. I do not believe this issue has any real significance given the state of the evidence.
14. As to the similar "misalignment" issue relating to a downstairs bedroom doorway referred to in [18](b), I do not find this to be of any consequence. The disparity from one end of the top of the architrave to the other is only 8 mm, and Mr Kingston's observation that there is a drop in the floor level to the west, explicitly assumes a new ceiling was installed at that point, something about which there is no evidence. There is nothing to suggest that any discrepancy had not been present since 1983. I should also observe that there are in fact three horizontal surfaces at play, a discrepancy at each of which or any combination could explain the differential. There is the top of the architrave itself, the cornice attached to the wall/ceiling joint, and the plasterboard no doubt attached to the ceiling battens. Photographs also reveal a crack running from the "lower" top of the architrave on the left at an upward angle from the corner.
15. I turn to par [19](a); the suggested previous repair of a crack in the eastern wall of the downstairs bathroom as shown in photographs taken by Mr Kingston. In cross-examination, he said he would not be surprised to learn that the crack in fact extended downwards to the left to the floor level, running behind a hand basin on that wall. He said that he did not note the crack to that extent and did not take photographs of that part. He agreed the crack was not the opening of a join in the plaster sheets but what he seemed to prefer to call a "distress crack", rather than a "tear" but in any case, agreed with the proposition that it was "a horizontal movement apart of the plaster sheet, [an] opening up of the plaster sheet." His explanation as to why the crack he observed suggested a previous repair is that close examination showed an outer jagged edge to the plaster work and wallpaper, but behind which was a smooth or even line in the inner edge. There is no evidence of loose plaster in the crack suggestive of patching.
16. Mr Kingston started to explain what the smooth line represents but interrupted himself to say that normally plaster fails and becomes jagged but when there is a smooth line behind the face of the actual crack, "like a knife has gone through it", that is evidence of previous repair. In the end, despite requests to explain why that is evidence of previous repair, no clear answer emerged that I could detect. In that state of uncertainty, it is not possible to take anything from this suggestion of previous repair.
17. The exchanges on this issue led to the broader issue of Mr Kingston's observations as referred to in par [19](e), inconsistency of cracking, internal to external. The discussion was focused on the particular crack, but the evidence is relevant to the general proposition. As I understand it, Mr Kingston's opinion as to previous repairs is based in part on the fact the internal cracking was much less than the adjacent external brick cracking. It was put to him that the greater movement in the brickwork was explicable on the basis that that was not tied to any structure, whereas plaster sheeting was nailed and glued to the studs. Mr Kingston acknowledged that it "could be the case" that the plaster, when it begins to tear apart, is inevitably not going to move as much as the unrestrained brickwork.
18. That brings me to the par [19](b) issue; the presence of mesh in plaster cracks suggesting previous repairs. There are several photographs in evidence which relate to the three different areas. Each photograph shows cracking on horizontal or vertical lines. In cross-examination, Mr Kingston was taken through the suggested ordinary plaster boarding progress. He agreed that plaster sheets have recessed edges to form butt jointing. He agreed that adhesive plastering tape is then run along the joint with jointing plaster applied over the joint to make the surface level which, when hardened, is sanded. He agreed that if the joint cracked open, one would see the mesh. When it was put to him this is what the photograph show, he replied, "Potentially. I mean, it - well, where I was - if you look at the external photos 27 and 28, I think they are. ... [They show] horizontal settlement of the brickwork on the other side of that particular crack ... ."
19. When pressed as to why the presence of mesh was evidence of a previous repair, and what that had to do with the brickwork outside, he said that it was almost in the same location and that they were reflective type cracks. Mr Jackson suggested this was not surprising as the building was moving in that area, Mr Kingston's response to which was that he could not be certain the crack was within a joint. At that time the focus was on a particular photograph but showing similar things to the others. The following exchange occurred:

"That's a joint in the plaster sheets, isn't it?......You'd have to measure it from the floor. Generally they're about 1.2, but it could well be, it could well be. I'm not just saying it's not, yes."

1. The end result of this is that, having regard to what the photographs show of the linear nature of the relevant cracks, taken along with the other evidence earlier outlined, I am satisfied that these areas are not areas of previous repairs in plaster.
2. I have already dealt with the par [19](c) issue in some detail. The evidence can be put no higher than the possibility of a previous repair. The cause of any previous repair is speculation. Mr Holmes was asked in cross-examination about areas of lighter and darker mortar on the downstairs bathroom eastern wall in respect of which, as noted above, the asserted inference is of a previous repaired brickwork crack, since re-opened. Mr Holmes agreed with the proposition that differences in mortar colour are suggestive of repair but explained that the reason for the repair can be many fold, and that it did not necessarily signify movement. He explained that the quality of mortar varies dramatically, and that it is not uncommon for repairs to be carried out because the mortar has eroded; re-pointing is done to prevent damage occurring to the brickwork. He pointed out that repointing is repair.
3. He further explained that the crux of the matter was whether in an area of suggested repair, the joints in the brickwork were relevantly even. He said he did not see anything at the time of his inspection in 2017 that suggested joint width was different. He saw very substantial cracking in discrete areas, "but nothing sprang out that we were looking at something that had extensive repairs carried out to it. Whilst there may be different coloured mortar does not necessarily reflect any serious damage had occurred to the property in the past."
4. Lastly, as to Mr Kingston's opinions in these respects, there is par [19](d), being the alleged previous mortar repair in the north-eastern corner brickwork of the downstairs bedroom on the southern-eastern side. This area is just the under a fixed canopy over a box bay window. As noted, he says Mr McDougall told him that he was not aware of the crack having been repaired since his purchase, Mr Kingston therefore concluding that it pre-existed 2010. Mr McDougall was cross-examined about what he had told Mr Kingston. He said it was not correct to say that he was not aware of the repair until Mr Kingston pointed it out to him. He said there had been a discussion about different colours in the mortar, but he was fully aware that this area had been re-bricked. He said he did not recall making the comment, "when I knew it had been repaired."
5. Mr McDougall had explained in his evidence-in-chief what had happened in the area. He said the renovation required demolition of the roof above the particular area and removal of the bricks to allow the insertion of a large laminated veneer lumber beam (LVL) which he said was actually a "double beam". Above where that beam now is, there was originally a veranda roof. To facilitate renovations in that area, brickwork had to be removed and replaced. In Mr Kingston's cross examination, he was shown a photograph of the wall in question taken by Mr Horsham during his inspection in October 2013. Mr Kingston agreed that differences in mortar colour were not discernible. He agreed it seemed there had been a lot of work done on and around the wall in question, including the removal of an old bay window. After being taken through the details of the likely reconstruction works, he was asked about the need for mortar repairs being necessary because the brickwork had been knocked. Despite the question, Mr Kingston said he thought it would be probably unlikely that the brickwork in would have collapsed but when the question was put again, he conceded that something could have caused it to crack.
6. Generally, I found Mr McDougall's evidence to be persuasive. Although there is a lot at stake for him, he did not appear to be inclined to exaggerate, and he made concessions where appropriate, quickly acknowledging possible deficiencies in his recollection. I am not satisfied that he told Mr Kingston that he did not know of the repair of the brick work in the relevant area, and I am not satisfied, to the degree the court is being asked to infer previous repairs due to cracked brickwork caused by movement of the building, that the different mortar colour is evidence of a pre-2013 repair of a distress crack.
7. On the whole of the evidence, I am satisfied the house was performing satisfactorily, if it can be put that way, at the time the renovations were commenced. As with most houses, settling and some minor cracking appears over time. Although it might be said that a house as purchased by the plaintiffs had been "patched and painted" for the purposes of sale, I am satisfied that nothing significant had then emerged in terms of significant movement of the building causing distress and damage.

1. The relevant events unfolded as follows. The plaintiffs engaged Mr Meredith as architect. He drew up a set of plans which was finalised with input from the plaintiffs. Mr Meredith asked Mr Horsham to become involved. They went to the site around 24 October 2012 at which time Mr Horsham carried out the inspection referred to earlier. Mr Meredith's drawings were the subject of an application for a development application granted in December 2012. Around that time, he became unable to continue. Further plans needed to be drawn for which Mr Horsham's engineering advice and detail were required. Mr. Horsham suggested getting a builder designer rather than architect, and recommended Greg Tilley. The plaintiff recalls a discussion with Mr Horsham about Mr Tilley's engagement. Ultimately it was the drawings prepared by Mr Tilley and certified by Mr Horsham on 6 February 2013 which were the subject of an application for building and plumbing permits.
2. In evidence is a quotation from the defendant dated 21 November 2012. I have already referred to two items noted as being part of the scope of works.[3] In addition, the scope of the work included the provision of hand sketches and markups to be documented by the architect and the preparation of documentation for submission to the council. In cross-examination the plaintiff said he would have contacted Mr Horsham to agree to the costing; he could not remember whether it was by phone or email.
3. Mr Horsham's evidence was that he provided the quotation after his initial inspection. He said that in it, he described what his "active scope of works" was intended to be and the cost. That cost was $1,850 plus GST. At the foot of the document is a recommendation that the client engage the firm to carry out structural inspections during the build, which are charged at $150 plus GST per visit. The document goes on to say that JSA typically inspect the footings and slab preparation, and reports are provided for the council or building surveyor, via email to the builder and client.
4. Mr Horsham said he did not hear anything for about three or four weeks after sending the quotation to the plaintiffs before Mr Meredith rang to say he was indisposed for four weeks. It was then that Mr Tilley was contacted. However, in later evidence he said he got a phone call from the plaintiff which related to his engagement, and in which the plaintiff said in effect, "Get on with it." That generally accords with the plaintiff's evidence. Mr Horsham also spoke to a building surveyor he had recommended to the plaintiffs, and arranged a site visit with Mr Tilley in January 2013. Mr Horsham said his initial responsibility was to assess and review the structural design shown on the Tilley drawings. He explained that he was to certify the structural components while the building surveyor was to certify the architectural documents.
5. Although coming later in time, there are further documents which shed light on the scope of the retainer. There is invoice dated 8 February 2013 from the defendant to the plaintiffs, two items of which are "Structural Design Review, Sketches & Certification - $1,850" and "Professional consulting services - $450". There is a later invoice dated 13 November 2013 for $247.50 which contains two items: "Mandatory Structural Inspection ... 27-6-2013 - $175.00" and "Form 55 - Inspections - $50.00". There is an inspection report from Mr Horsham dated 27 June 2013, in evidence but which the plaintiff said he did not see. That refers to "Inspection of footing preparation for decks and kitchen extension" and "Inspection of steel & timber framing for lower and upper storey".
6. A Form 55 is a "Certificate of specialist or other person (building work)". The purpose of the form is, as may be expected, to certify specific aspects of building work, and is an important part of building permit application process. There are two in evidence, the first dated 6 February 2013, the second 13 November 2013. The "Certificate type" in the first one is described as "Structural" with "Structural inspection" appearing in the second. Relevant documents are noted in the first as certified design drawings for the plaintiffs by Greg Tilley dated 4 February 2013 and certified by the engineer on 6 February 2013. The second refers to "Inspection records dated 27-6-2013".

1. The pleaded case is that the defendant was retained by Mr Meredith, but the defendant accepts that the evidence shows otherwise. I find that the plaintiffs directly engaged the defendant. The next thing is that this is a claim for economic loss as distinct from, and not consequent on ordinary damage to property: Bryan v Maloney (1995) 182 CLR 609 at 617-618; Woolcock Street Investments Pty Ltd v CDG Pty Ltd [2004] HCA 16, 216 CLR 515 at [19]- [20], Makawe Pty Ltd v Randwick City Council [2009] NSWCA 412 at [128] and De Pasquale Bros Pty Ltd v Cavanagh Biggs & Partners Pty Ltd [1999] QSC 171, [2000] 2 Qd R 461 at [54].[4] The defendant accepts it had a duty of care in respect of such loss - foreseeability of injury is accepted - and there is agreement as to how that duty is to be broadly expressed. Based on cases such as Voli v Inglewood Shire Council [1963] HCA 15; (1963) 110 CLR 74 per Windeyer J at 84 and Brickhill v Cooke [1984] 3 NSWLR 396 at 399, the duty is formulated as one to exercise such care as would be shown by a reasonably competent and ordinarily skilled and qualified engineer retained for the purpose in hand.
2. However, there is a marked divergence in relation to the scope of the duty. The defendant's case is that the duty is further confined and only extended as far as the performance of the services the subject of the contract; that is, the duty was one only with respect to the tasks contracted to be done and performed for the extension. The defendant says it does not seek to ignore the existing footings because "inevitably, they have to be taken into account", but argues it was not engaged to redesign the dwelling as a whole nor carry out a building superintendent/project supervisor type role. It is said that the task was to provide input adequate for the extension, and the reference in the quotation to designing footings has to be restricted to those few footings supporting the extension. Accordingly, there was no obligation to redesign the existing footings and, "... any duty of the defendant was limited to understanding and accommodating the capacity of the existing footings, as situated within the soils identified by a reasonably conducted investigation, for the [designed] extension."
3. In closing submissions, the defendant did not argue the point in any greater detail and the plaintiff seemed to proceed on the assumption that the duty was of the broader scope. There is no reason to think other than the proper approach to the issue is the same as would be taken in relation to the existence of a duty of care in an economic loss case. That question was recently the subject of consideration by the High Court in Mallonland Pty Ltd v Advanta Seeds Pty Ltd [2024] HCA 25, 98 ALJR 946. There, at [33] of the plurality judgment, the criterion of assumed responsibility was confirmed as a basis for the existence of a duty of care notwithstanding criticism that had been made of the term. Further "salient features"[5], the presence of which may indicate a duty, were discussed at [38] and following. Actual or constructive knowledge of a risk to a person or class of persons of the particular type of economic loss that eventuated and the magnitude of the economic loss that risk entails, strengthens the case for the finding of the duty of care.
4. Another matter that has been identified is a plaintiff's vulnerability to the type of economic loss that eventuated. A mere likelihood of suffering economic loss if reasonable care is not taken will not amount to vulnerability, but the point is the plaintiff's inability to protect themselves that eventuated as a consequence of a defendant's carelessness, either entirely or in a way that would cast the consequence of loss on the defendant. Reliance was not separately considered in Mallonland, but it may be seen as part of the concept of an assumption of responsibility although absence of reliance is not necessarily fatal to the establishment of a duty of care: HXA v Surrey County Council [2023] UKSC 52; [2024] 1 WLR 335 at [90], [108]. Reliance may be taken as established where there is a relationship between a professional person and the client: Pullen v Gutteridge Haskins & Davey Pty Ltd [1993] VicRp 4; [1993] 1 VR 27 at 39-40.
5. The plaintiff's case relies on the existence of a duty arising in the context of an undertaking to engineer an extensive range of alterations, not only to the main part of the existing building at ground level, but more significantly it might be thought, to the addition to the existing structure. That structure amounts to a much bigger second level - with bath, glass shower partitions, tiling etc - in place of a very lightly constructed partitioning of an attic. The plaintiff says it is impossible to ignore the overall purpose and effect of the renovation project that was undertaken. The plans show that the expanded upper level increased the floor space of that level by about 62 per cent. In his evidence-in-chief Mr Horsham described the new upper level as a "storey", but in cross-examination he very strongly disagreed with calling it such, but I note that Mr Kingston seemed quite comfortable in continually referring to it as a 'storey'.
6. For those reasons, I need to look at Mr Horsham's evidence. He said that Mr Meredith had done quite a detailed section in his development drawings which was useful because he had done the hard work to assist him, as a structural engineer, to work out what Mr Meredith's intention was. In the preliminary discussion with the plaintiff, Mr Horsham advised he would be assisting Mr Meredith "to put together a set of working drawings from which the project could be built" [My emphasis]. More particularly, he later said that, although with some reluctance because he assumed the building surveyor had carried out his own inspections, he completed the Form 55 certificate dated 13 November 2013 which referred to an inspection and report dated 27 June 2013. He said, "I didn't do this lightly, but I was satisfied with what I had seen that I could give the building surveyor some comfort that "I was satisfied the works were fit for purpose" [My emphasis].
7. In addition, there is the evidence I have already mentioned; that is, Mr Horsham said that one of his concerns was with the weight of the building and what was carrying the load. Obviously, that concern would be carried forward into the advice and design input he assumed responsibility for and chose to give. Mr Horsham gave evidence of a site visit in March 2013, during which he had the opportunity to inspect a part of the existing footing on the eastern side. He said he told the plaintiff that the footing was a suitable depth and was sitting in good material; "I was quite clear on this, I said in this area I was satisfied that we wouldn't require to do any additional works to those footings." Further still, in cross-examination Mr Horsham agreed that the request to inspect demolition, footing preparation etc set out in the Form 55 of 6 February 2013, was prompted by the design of the building and its height.
8. On one view, the broader scope of the duty might well have arisen simply because of the language in the quotation. That describes consultation on engineering design generally and is not confined. "Designing" is not confined to the footings but covers timber and steel framing, which was to occur in both upstairs and downstairs, and roof modifications. The whole of the extensions and additions would accordingly be encompassed. In any event, it is clear, and I find, that on the evidence the defendant, through Mr Horsham, assumed responsibility for giving advice and design work for, and to enable, the renovations as an entire exercise; to draw plans "from which the project could be built." In that respect, there was reliance by the plaintiffs. It is not at all clear to me quite what counsel for the defendant intended by the concession that the existing footings had to be "taken into account".
9. The defendant knew or ought to have known of the risk of internal distress to the building with consequent economic loss if the completed renovation works were "not fit for purpose." To the extent it is necessary to go further, in the circumstances of the respective positions of the plaintiff's and the defendant, the plaintiffs were vulnerable to the type of loss suffered.
10. As the focus is on the adequacy of the footings of the building as a whole, it might pay to note that in Woolcock Street Investments Pty Ltd v CDJ Capitals Pty Ltd (above) at [76], McHugh J observed that courts "have long held that engineers engaged in connection with the design of a building have a duty to examine the site to see whether the nature of the sub-soil is adequate for the proposed building". Inextricably allied to that is the question of design. It is not a large step at all from the design of a new building to that for an upper level on an existing building. Of course, questions of the scope of a duty of care and are not to be judged with the benefit of hindsight having regard to the outcome. All things considered, I hold that the scope of the defendant's duty extended to consideration of the suitability and sufficiency of the existing footings, and to carry out such examinations and investigations, including soil investigations as may reasonably have been required, to ensure they "would be up to the task" as it was put. And if not, to determine what work might be needed to achieve that and advise accordingly.

AS 2870-2011 - Residential slabs and footings

1. The 2013 alterations and additions to the property were the subject of the provisions of the Building Act 2000. Section 55 of that Act provided that building works was to comply with the Building Code of Australia (BCA), in addition to the Act's provisions. The BCA is to be found within the National Construction Code. Under the BCA, Australian Standard 2870-2011 (the Standard) is an "acceptable construction manual". Compliance is necessary unless the proposed works are based solely on performance solutions. The defendant places heavy reliance on the Standard in its argument about breach of duty. It is best to explore it now.
2. The stated objective of the Standard is to specify performance criteria and specific designs for footing systems for foundation conditions commonly found in Australia and to provide guidance on the design of footing systems by engineering principles. Clause 1.8.25 provides that a "footing system" is "a general term used to refer to slabs, footings, piers, and pile systems that transfer load form superstructure to the foundation." Section 2.2 deals with "Methods for Site Classification". Clause 2.2.2 provides that site classification based on identification of the soil profile is to include one or more of specified methods. Relevantly, cl 2.2.2(b) refers to "Identification of the soil profile and interpretation of the current performance of existing buildings" and continues:

"The soil profile shall be confirmed by inspection of soil from a bore hole(s) or other excavational sampling method in accordance with Clauses 2.4.3 and 2.4.4. Interpretation of the performance of existing residential footing systems within the region that are not less than 10 years and are founded on a similar soil profile shall be in accordance with Table 2.2. ...".

1. Table 2.2 deals with "Classification of normal sites by the interpretation of footing performance of existing buildings". It does so by reference to the degree of damage to existing walls. In the case of masonry veneer, which this building is, site classifications may be 'S', 'M', 'H1', 'H2' or 'E'. In this case it is not contentious that the site classification for the property is 'M'; that is, moderately reactive clay or silt which may experience moderate ground movement from moisture changes. Clause 2.4 deals with "Site Investigation Requirements". Clause 2.4.5(a) provides that the determination of adequate bearing strength is to be considered on the basis the design bearing capacity of foundation level is to be not less than 100 kPa for strip and pad footings. A footnote to clause 2.4.5 provides that determination of bearing capacity is to consider the weakest state of the foundation under normal site conditions, with local knowledge to be used where available.
2. The subject matter of Section 3 of AS 2870 is "Standard Designs". Clause 3.1 is entitled "Selection of footing systems". There is some debate about the application of cl 3.1.5 - "Design for outbuildings and extensions to dwellings" which provides that the footing system design given in the section "shall be used for outbuildings and extensions". An "extension" is defined in cl 1.8.19 to be an "Additional construction abutting an existing building." In any event, cl 3.1.5 goes on to provide that footings of similar proportions and details to those used in an existing building on the same allotment may be used, provided the performance of the existing building has been satisfactory over at least 10 years after construction and there are no unusual moisture conditions. By cl 3.3, in the case of site classification class "M", footings for masonry veneer structures are to be 500 mm deep by 300 mm wide with the top of the footing to be 500 mm below finished ground surface level.
3. The Standard has a commentary section which provides explanations for the operation of various clauses. That for cl 3.1 contains a table of typical applied bearing pressures under strip footings. For a single storey masonry veneer building, it is 50 kPa; for a double storey it is 65 kPa.

1. There is no dispute about the fact that Mr Horsham inspected the property in late October 2012, as I have previously outlined. Further, although Mr McDougall seemed uncertain about whether it was June or July 2013, there is little doubt that on or near 27 June 2013, Mr Horsham inspected the ongoing renovations leading to the previously mentioned written report bearing that date. However, there is no consensus between the plaintiff and Mr Horsham as to the timing or circumstances of any other site visits or inspections between when the demolition commenced on 1 March 2013 and the completion of the project. At the heart of things is Mr Horsham's evidence that on two occasions he was able to inspect existing perimeter footings, with a particular opportunity on the first occasion to assess soil type. It is not so much the timing of these inspections which is an issue, but rather the question of what he inspected or saw, or was able to inspect and see, and what conclusions could reasonably be drawn. That said, credibility does have a role to play and questions of timing and how the visits were characterised by Mr Horsham have relevance to that issue.
2. I will start with Mr Horsham's evidence as to starting on the project and how he approached his tasks. Some of his evidence does not easily bear summarisation; it is best set out and left unedited. Having described his inspection of the house in October 2012 and his conclusions as to its integrity, his evidence-in-chief continued as follows:

"Did you have any discussion with Mr McDougall at this time about the assessment of ground conditions and footings?......I did. I did. There was discussion - I might stray for a moment. Architects are terrible about discussing the cost of a project with a client, and typically I raise the question about what the intended budget was. The reason I do that is to assist me in scoping what my fee structure's going to be, because as a guidance, I - I charge typically a percentage. And because it's an existing house and the extension was predominantly in the centre of the house, the areas were covered with decks. And I made a comment that I thought the foundations were in good condition given that the house was 25 years old, and that I could see no visible stress, aka movement in the masonry. But I did say that you've always got to consider a contingency, because until I actually see the foundations myself, we've just got to assume that they may need some work. And then there was a discussion about what that work may entail, and I said, 'Well, it's - it's typically - there's a few methods available, but typically it's a process called underpinning, where you may be strengthening the footing.' But I said that it's difficult to predict the cost of underpinning because you have to be careful that you don't underpin one section of the house because you can actually cause more damage, and typically when underpinning is done it's the entire house, because you're trying to stabilise the entire strip footing. And then a - I can't remember if I offered it or if it was asked. I said, 'Look, if worse' - I said, 'Worst-case scenario, it might cost, like, an extra hundred thousand dollars'".

1. He said that conversation did not end very well, but no further detail was given. Mr Horsham was asked whether he had arranged a soil test. He said he did not at that time because he "was not engaged." After describing at some length the course of events leading to Mr Tilley taking over from Mr Meredith, Mr Horsham was asked about the visit to the property in January 2013 with Mr Tilley. Mr Horsham said he had arranged that with Mrs McDougall. He and Mr Tilley went to the property, but he could not recall who was actually there at the time.
2. Mr Horsham was asked whether he again inspected the property when he went to the site with Mr Tilley, and then whether he made any assessment or classification of the soil and its bearing capacity. His answers to these questions were very lengthy and discursive.[6] He referred to the "Code" instead of the Standard as such, but the intent was plain. What can be gleaned is as follows. He had a copy of a geological plan which gave him an understanding of the underlying geology. From that, and his inspection of the area, he knew he was dealing with soils and not rock. He said he had 25 years of data by way of the house, with the Code providing for making an assessment of how the existing foundation has performed and what that equates to in soil reactivity. This seems to be a reference to cl 2.2.2(b) despite the reference to soil reactivity[7], and although that clause refers to the performance of existing residential footing systems within the region that are founded on a similar soil profile. Having assessed the condition of the house and with the benefit of the geological plan, he assessed the site as class 'M'. (As earlier noted, that classification is not in dispute.)
3. Mr Horsham was then asked whether he designed or reviewed the plans with a bearing capacity in mind. The following exchange occurred:

" So, at that stage, we're - I'm still sort of - I'm still mid-January. The actual foundation design happened a week or two later. Did you want me to lead to that or -

Yes?......Yep, okay. So, again you have to keep in mind that AS 2870 was developed I believe in the mid-'80s, refined a few times, but in effect, it's - it's taking actually an economic view of foundation design. And there's some interesting commentary inside it, but in effect, it - engineers are like this. They put a - an economic cost to the country of - you know, why don't we just design every house with two metre deep footings? So, we don't do that, and in effect, what AS 2870 allows you to do is to design alterations based on some sections in the Code. So, I think it's - there's a clause - so - so my point is, the Code is written for new houses primarily, and there's a tiny little paragraph which is quite common with the Code, all the good stuff's hidden. But there is a tiny paragraph, I think it's clause 3.1.5 in the 2011 version that says:

For alterations and additions, that for a clad-framed house or extension to a dwelling -

You know, what does clad-framed mean? Clad-framed means lightweight construction. Weatherboards over timber. Highly flexible. For a clad-framed extension, you can actually take the soil classification back a step. So, if you've said it's an M, if you're doing a clad framed structure, you can actually say it's an S. Now, that's in clause 3.1.5. Now, it also says for masonry veneer extensions. And I'm sure there's been great debate over whether this is a single or a two-storey or whatever, but principally, AS 2870 says this is for the design of class 1 dwellings. Class 1 dwellings being residential. You can also use it for sheds and extensions. But principally, it helps the design. It helps the designer because again, keep in mind, I'm a specialist. I'm a structural engineer, a lot of people don't realise this, but AS 2870 can be used by a lot of different building practitioners. So a lot of people don't realise this, but you don't actually need an engineer to design your foundation if it's M class or less. So why is that relevant? Because there's some juicy stuff in the Code that possibly only engineers understand, and there's some stuff for the lay person. So typically, that Code is deemed to satisfy. So deemed to satisfy footing and slab design for residences. Now, drawing to your question on bearing capacity. So a Code is meant to make the process of design two things, in my opinion. Efficient and standardised. Efficient and standardised. So the Code actually tells you in its commentary. So the cool thing with the Code is you've got the standard and then you've got commentary. And in the 2011 version they've put the two together. So the commentary gives you some assistance to understand it, but the actual Code tells you that these designs are based on certain bearing capacities. So there's a little table in the - in the commentary that says if you've got clad framed, if you've got brick veneer, or if you've got full masonry, double masonry, you - they give you numbers in kilopascals, so pressure, as to what you would anticipate those footings being able to withstand. So in effectively [sic], it says, you know, for a single storey brick veneer it might be, say, 50 kPa. If it's double storey, it will bear about 65.[8] Now, let's just be clear on this. The Standard actually tells you that these are the weights that you're going to get with a full storey, two-storey house. So this is two levels of - of brick veneer. It states that you'd expect to get about 65 kPa. Now, why is that relevant? Because you know that, for a - the Code also tells you that for a slab on ground - and slabs typically are used where you've got softer material. So we use slabs to distribute force, distribute pressure, and -

Perhaps if I can just interrupt you there?......Yep.

What - what bearing capacity did you - ?......Yes.

- this project?......I almost got there. So a slab allows you to design for 50 kPa, and it say, however, if you're doing footings, so isolated footings, and they assume that - or the Code, again, to make it simple, states everything's 300 millimetres wide. So based - these - these likely bearing capacities based on a 300 mil wide footing. And they -and it states that you - you need to - that you - you can't put them in anything less than 100 kPa[9].

Right**. And is that the - the number that you used?**......Yes, it is. And you know that because of the condition of the property." [Emphasis added]

1. Mr Horsham went on to explain that the Code says that what is to be expected in terms of loading on a strip footing for that type of building and based on his assessment that the house was in fairly good condition after 25 years, he "made the call" that the bearing capacity in the area, without seeing the footings at the design time, was achieving that.
2. The following seems to have been involved in the approach to design. Mr Horsham first had recourse to cl 3.1 .5 - Design for extensions to dwellings - which enables the use of footings of similar proportions and details to those used in an existing building on the same allotment, provided there has been satisfactory performance over at least 10 years and there are no unusual moisture conditions. That led to the commentary to cl 3.1 which gives 65 kPa as the typical applied bearing pressure under strip footings for a double storey. The exercise then went back to clause 2.4.5(a) which prescribes a design bearing capacity at foundation level of not less than 100 kPa for strip and pad footings. Mr Horsham used that minimum figure. The statement that this bearing capacity was used or prescribed for "this project" is ambiguous. It might mean the design of the new footings, or it could relate to an assessment of footings for the whole of the existing structure. Counsel for the defendant did not explore the matter further but went on to lead evidence about site inspections. I will return to this point.
3. The evidence about Mr Horsham's inspections of the original footings is as follows. In evidence-in-chief he said that he became aware that work had commenced around 13 March 2013 when he was driving to Woodbridge and saw a tarpaulin on the roof of the house. That indicated to him that demolition was under way, and he needed to see that part of the works. He went there the next day. Both the builder and the plaintiff were there. A section of the deck on the eastern side had been removed which gave him an opportunity to look at the existing footing at that location. The builder took a spade, the footing was relatively close to the ground, and he dragged the material away. Mr Horsham saw it was relatively loamy material at the top "getting stiffer" and he was able to see firsthand the concrete strip footing at that point.
4. When asked whether he tested the soils in any way, he did not directly respond, but said he was in close proximity to the ground and could tell by the way the material was being removed that it was extremely hard. He used his experience and visualisation to see that there was no moisture; it was very, very dry, having a gravelly clay consistency. He thought it was good material and explained why the house, being the age it was, was in good condition.
5. Mr Horsham also said Mr McDougall was digging a hole in preparation for a pad footing. He asked Mr McDougall how hard the ground was and was told it was "very hard". He told Mr McDougall that the footing he inspected was at a suitable depth and was sitting in good material: "In this area, I was quite - quite clear on this, I said in this area, I was satisfied that we wouldn't require [sic] to do any additional works to those footings.".
6. The next visit was said to be a formal inspection on 27 June 2013. Some things were discussed with the builder. After that there was a visit in mid-July when he was invited back for a further look at things. Mr Horsham said he saw footings on the north-west side associated with the kitchen extension. He took photographs but the SIM card malfunctioned. He described the condition of the soil as excellent. It was dry with sandy loam on the top, the same gravelly clay type of material that had been seen on the eastern side. The next visit after that was in November 2013 after the plaintiff rang him and said the building surveyor wanted a final inspection. Mr Horsham said that this did not make him very happy as he thought the surveyor had been carrying out his own inspections. After consideration he issued the last Form 55 certificate.
7. Before cross-examination about visits and inspections, questions were asked about some preliminary matters. First, Mr Horsham denied that he knew Mr Tilley was not aware of the footings that existed under the original structure[10], but agreed that although Mr Meredith's plans show detail of the footing locations, they were shown as just having a nominal depth. He agreed that where Mr Meredith's drawings have references to footings, there is the notation "to structural engineers design".
8. Mr Horsham was reminded of the quotation which indicated structural inspections would be carried out and was asked whether it was correct that he had only ever provided one inspection report; that dated 27 June 2013. Mr Horsham disagreed, saying the Form 55 certification "was a cover-all document". He was asked about other reports and said that "The other three inspection reports [sic]...weren't inspections. The very first visit to site, for example, was just a preliminary, effectively talk to Mr McDougall and the builder. That wasn't an inspection, as such." There followed this exchange:

"The March inspection was. In fact, it was an inspection you specifically requested permission to make?......That's not correct.

Oh, I'm sorry. I thought you told me you were driving past the property, saw a tarp up there, rang Mr McDougall and asked if you could come and inspect it, and he said, 'Fine', and you did so the next day. Wasn't that your evidence?......I don't agree with you - your terminology. You're implying it was an inspection. It effectively was a visit to site to meet the builder and the client and to assess how far they had got. That wasn't an inspection."

1. Mr Horsham said he thought there were two visits in July, a couple of weeks apart, which he was happy to call site inspections. No report was produced from either; he said it was in the "cover-all" Form 55. He took photographs on both inspections in July but lost them sometime in between July and November in that year, although he did not lose the June ones. There was no other record made of the July visits.
2. Mr Horsham was then taken to the entry "Footings and concrete padding inspection 27-6-2013" in the Form 55 certificate dated 13 November 2013. He did not agree he was intending to certify to an inspection of footings and concrete pads on that date but said "[I]t's implying that it's in reference to the report [sic]", the report being the one of 27 June. He was asked what he was intending to convey when he wrote those words. He said it was just to say that he done the report, not certifying the carrying out of those inspections, but "referencing the document"; it referenced "the report of the same date, or at least the photographs within that report".
3. I confess to having difficulty following his evidence. The report refers to "Inspection of footing preparation for decks and kitchen extension." Mr Horsham was asked as to when he inspected footing preparation for the decks. His reply was that it was earlier than, or in a different timeframe to, the kitchen. The question was put again. He said it would have been in two time periods, one in March and one in July. When asked about inspecting footing preparation for decks in March, he said that it refers to the "deck column" being the one he described as Mr McDougall preparing, and about the soil on which Mr McDougall commented.
4. Mr Horsham agreed that his request noted in the first Form 55 in February 2013 for an inspection of demolition, footing preparing and framing was, as evident from the document, prompted by building design and height. He confirmed the demolition was underway when he went to the site in March. He did not inspect the demolition because he repeated that it was not a request for him to inspect the demolition, it was him introducing himself to the builder. He also agreed that although driving past on the previous day and seeing the tarpaulin on the roof raised some concerns, he did not in fact inspect any demolition when he went. He said, "It wasn't an inspection".
5. When asked what he actually did on 14 March, Mr Horsham said "So this project required good communication between myself and the builder." He was asked again what he actually did, to which he replied that a strip footing was exposed with the builder's assistance. This was one relating to the dining room extension. When pressed about whether that was actually in March, he said he could not honestly say that it was on that day; it was sometime between 14 March and 27 June, that he could not categorically say that he went back at some time in that period. He could not give a date as to when it was, he thought the builder scraped away some dirt from the existing footings. Some cavilling about the nature of the March visit continued. When referred to the note about periodic inspections in the second Form 55, Mr Horsham conceded that it included the March visit. Later however, he repeated his assertion that he did not go there at that time to inspect demolition progress and did not do that when he was there. The purpose of the visit was to introduce himself to the builder.
6. During questioning, the reference to the builder scraping away dirt changed to an assertion that the builder dug a hole to expose the footing. Mr Horsham said that he was satisfied that the hole that was dug gave sufficient information to verify "at that point in the house" that the ground material had good bearing capacity. He did not get the builder to dig another hole somewhere else around the building perimeter because that was to be at the time when the footing for the kitchen extension was to be prepared. On the visit when he saw the footing for the kitchen extension a hole had been dug, effectively he agreed, under the point where existing French doors opened onto the sunroom that Mr Bryant had built. Mr Horsham said he was not aware that it had been built in 2004.
7. It is clear from the cross-examination on the contemporary photographs that the hole which Mr Horsham was then looking at was one dug down beside the concrete slab for the sunroom extension. When it was suggested to him that it would say nothing about the existing footings of the house, Mr Horsham said the point was that he was looking for bearing capacity; material "that your're founded into." When the question was pressed, he said that he could understand the point, adding that you could not exclude the newer part of the building as part of the works. However, he agreed the sunroom was largely unaffected by the new renovations in terms of the additional loading.
8. Following on from the cross-examination about what Mr Horsham actually looked at, he was asked questions about what he did not do. In the context of the inspection of the point next to the sunroom, he disagreed with the proposition that a more productive location to examine the existing footings would have been at the other end of the building. This disagreement was based on the fact that there were no additional loads being put over that area. He disagreed with the contrary view expressed by Mr Holmes. He said that in terms of a percentage of what was there, the addition of greater structure elements was relatively small. Going back to the inspection of the edge of the 2004 slab, Mr Horsham said that he had seen the column preparation which was only a few metres away, he could see the footing at the dining at the extension and was satisfied that he did not need to see anything further.
9. As to the inspection of the footing near the dining room extension, he said that he saw that it was 300 mm deep and found it in the gravelly clay material. He said that it was not necessarily the case that the new footings to be installed had to be at least 450 mm deep under the Standard. The following exchange occurred:

"Class M requires for masonry veneer a depth of 500 and a width of 300, doesn't it?......Yes.

Yep?......You're - you're referencing the table here? Yes.

If you'd been building this house in 2013, to the design - to the 1983 design, you'd - those are the footings you'd require, aren't they? Once you were satisfied of the class M site?......No, that's not correct.

Why is it incorrect, Mr Horsham?......Well, in this - if you look at the elevation of the - did you call it a living room, dining room? Are we agreed - a living room that it's - there's no - there's no masonry at the top of it.

I'm sorry, there's no - ?......There's no masonry.

I'm talking about the entire house, the footings around the perimeter of this entire house. The strip footings would have been required if you were building it in 2013, to be those dimensions, minimum?......I disagree.

Do you just ignore the standard?......No, that's incorrect, I actually comply with the standard clause 3.15.

So what do you say that clause 3.1.5 tells us that's relevant to the proposition that I'm putting to you?......May I have a copy?

[The witness was referred to a page in the court book]

[M]y first question is, Mr Horsham, if you were building the original building to the original design in 2013, the standard would require you to have those minimum sized footings that I've just put to you, from the table. And you said, "No", and then you referred to 3.1.5, I think?......Which I haven't got it. I need the second page please

[An additional page number was given and cl 3.1.5 read out]

[M]y point is this. You don't have an existing building - you've got a vacant block of land at 3315 Channel Highway, Woodbridge. If you came along to build a house on it to the design - the 1983 design, your footings would have been required to be a minimum of - according to the table?......I'm not going to speculate on that. I think that's an unreasonable proposition.

That's what the standard says, isn't it, Mr Horsham?......I've just read the part of the standard, yes.

Sorry?......I've read the part of the standard that I was referencing as part of my design.

HIS HONOUR: But that's not the question. The question is a hypothetical one. If you were building the original structure in 2013, you would have had to go to the standards and the table we were looking at for the depth of the footings.

WITNESS: Yes. I agree, that's the approach but I don't - I'm not - I don't wish to put forward a design for a hypothetical house."

1. Mr Jackson then moved to the application of cl 3.1.5 and suggested that the relevant table gave dimensions for footings if a ground level extension was being built. Mr Horsham agreed that this was correct as a starting point. Counsel pointed out that cl 3.1.5 does not specifically deal with the situation where what was being built amounted, in practical terms, to a new storey, and on that basis the importance of knowing what was there by way of existing footings could not be ignored. Mr Horsham disagreed, simply saying that this was not a new storey.
2. Lastly, when further questioned about the ease with which other parts of building could have been checked by simply digging a hole against the wall down to the footing, Mr Horsham repeated that he was satisfied with what he had seen. It was "not necessarily" the case that he could easily have done what was suggested. When asked about what he meant by that he said, "Well, the opportunity presented itself because [the builder] was working in the area."
3. There is a report in evidence prepared for the defendant by Dr Wayne Griffioen of Tasman Geotechnics dated 7 June 2024, although Dr Griffioen was not called. On his investigations he established that on the south-western side of the building the strip footing was only 200 mm deep and 280 mm wide[11]. Mr Horsham said that he would not have been concerned had he known that in 2013 as to whether the proposed extension would be supportable. He was not concerned that the building was to be overloaded because the 25 years' performance was sufficient evidence that the footings were satisfactory for what was being proposed. He disagreed with the proposition of the risk of overloading the footings. He said he was satisfied where the main loads were on the house, and the inspections he had done and the material he saw gave him confidence.
4. Apparently, he used a computer program to calculate what sort of extra weight was being put onto the building. Subsequent questioning went as follows:

"What sort of weights did you come up with for the total new structure**?......I didn't do a total new structure calculation.** So I concentrated on the area on the eastern side.

So do you have any recollection at all of reaching some calculated assessment of the likely weight of the new upper storey?......Yes, and it was far less than what the Code stipulates as being allowable.

Yeah, but can you give us a figure?......No, I can't. It's -

You would still have those calculations?......No, I don't.

Mr Holmes, I can tell you, calculated that the additional flooring timber joists, the new joists that were to go in alone, were a total sum of two and three quarter tonnes. Would you dispute that?......I - I can't recall.

Did you ever do any calculation of that kind?......Typically weight of the structure is far less than the dead and live load applied.

Sorry?......So, calculating the weight of a house you'll find that the actual live loads are far in excess. So, generally there's a - an allowed loading for a - for a floor.

Let's be clear, dead weight is the structure - structural elements - ?......Yes.

Live load is things like, people, furniture - ?......Yes.

- and things you put into storage areas that might be moved around. They're transient loads?......No. ... No, that's dead loads". [My emphasis]

1. Mr Horsham was taken to Mr Holmes's calculations as to the structural elements. He disagreed with the proposition that a substantial weight was to be added to the upper storey. When queried whether that imposed no extra load on the building, he replied, "Houses - houses weigh tens of tonnes". When pressed about the extra load on the building he said that it posed a load that was satisfactory.
2. I have set out this evidence in some detail, as an appreciation of what Mr Horsham did and did not do is the critical question. The way he gave his evidence is also important. I have to say that I found him to be an unconvincing witness. With due respect, there were many occasions when he was discursive, didactic and unresponsive to the question, preferring to argue and qualify. In closing submissions, counsel for the plaintiff suggested it might be doubted that Mr Horsham examined any part of the existing footings at all but argued the case on the assumption that his inspections were as outlined. On balance, I am prepared to so find.
3. It might be expected that Mr Horsham would have inspected the footing near the dining room extension because the plans called for that footing to be connected to a new strip footing and the dimensions of the existing footing have some relevance in that sense. The hole in the ground in the location of the kitchen extension would have revealed nothing about relevant footings, although it provided an appreciation of the nature of the soil. That said, there is no evidence as to how deep the top of the footing on the eastern side was below ground surface level, nor of the depth of the hole on the northern, or kitchen, end of the building. (I should here note that the proposed new strip footing for the kitchen extension was not proceeded with but substituted, with Mr Horsham's approval, with one or two pad footings.)
4. So much for the nature of the soil. As I have mentioned, there is ambiguity in what Mr Horsham said about to what aspect of design the figure of the 100 kPa was applied. It is implicit in the defendant's argument that such design bearing capacity was used in respect of the existing perimeter and other strip footings. Assuming that to be so, there is still the question of whether the building design and construction materials used for the upper level would result in an overload on those footings in any event. It will be recalled that this was touched on in cross-examination. It is possible that Mr Horsham considered the bearing capacity of the footings on the eastern side of the house where there was to be a new strip footing, but I am not satisfied that the exercise in relation to the load imposed by the extent of the upper storey was considered in any reasonably purposeful way.
5. The passage I have set out in par [91] above - and which in my view contains a clear contradiction - does not inspire confidence that any meaningful calculations were done. The issue was not raised in evidence-in-chief and only emerged in cross-examination.

1. As ultimately put in the plaintiff's case, the question is whether there was a breach of duty by failing to exercise the level of care and skill to be expected of a reasonably qualified structural engineer by the failure to carry out adequate investigations of the dimensions of the existing footings and the ground conditions in which they sat. This, with a view to seeing whether the existing footings were sufficient to support the loads likely to be imposed as a result of the additions.
2. In Mr Kingston's report of 14 June 2022, after setting out a description of the building on site, and noting that the Standard was first introduced in 1986, he says:

"Residential footings designed and constructed prior to the introduction of AS 2870 are known (at least by structural engineers) to be often of a lesser standard than those designed to AS2870."

1. His position on this in cross-examination is interesting. He first confirmed the common ground that the house was built in 1983 and therefore not built to the Standard. It was then suggested that it was also known, "... because I think you have told us, that buildings constructed in that era ... are known to have, not infrequently, insufficient foundations." He replied "I don't think I said that. But if - it can - it can occur, yes, yes."
2. Mr Kingston's cross-examination continued into the next day, and counsel returned to this point. Having read out the extract from the report as requested, Mr Kingston was asked to confirm whether it was his view, he said, "It can be, yes. I have no reason to doubt it. It just depends on the day you have - whether an engineer was actually involved in the design of the footings or not." In answer to the question of whether that was something known by structural engineers in his experience, he answered "To design footings as best they can to the available guides at the time?"[sic]. Despite the enigmatic and obscure answers, I take it that Mr Kingston adhered to his report.
3. When asked about this statement, Mr Holmes said he did not think it was valid, but his explanation effectively put him in the same position as Mr Kingston. Mr Holmes said the benefit of the Standard was it recognised there were differences between sites, and there cannot be a single footings system that will work on every site. He said that it did not mean that old footings were necessarily inappropriate and was smaller than they needed to be.
4. The defendant largely relies on asserted compliance with the Standard as it relates to site conditions. It argues Mr Horsham acted in accordance with a reasonable interpretation of cl 2.2.2(b), in examining the house of signs of movement and inspecting the soils during construction. I have already commented on the latter. In terms of cl 2.2.2(b), the "reasonable interpretation" can be taken as a reference to Mr Holmes's agreement that an examination of the residence the subject of the project would fall within the provision. But I take the view that the terms of the clause are plain enough; it relates to existing residential footings systems within the region on not less than 10 years vintage and which are founded on a similar soil profile. In any case, it is not the site classification as such that is an issue. Leaving aside the requirements of a determination of adequate bearing strength set out in cl 2.4.5, site classification leads to what parts of section 3 - Standard Designs - are applicable; in this case cl 3.6 - Strip Footings, class 'M' - masonry veneer. In that context, the defendant argues that there was nothing to put Mr Horsham on notice of any factors relevant to the site calling for caution.
5. It is perhaps worth noting that under the Standard, the next classification class after 'M' is 'P'. The characteristics of that class are set out in cl 1.3.3 which relate to abnormal moisture conditions, being conditions other than those caused by seasonal and regular climatic effects and normal garden conditions. Under cl 2.1.3 sites with inadequate bearing strength or where ground movement may be significantly affected by factors other than reactive soil movements due to normal moisture conditions, are to be classified as 'P'. In particular, a site is to be classified as class 'P' if, among other things, the bearing strength is less than that specified in cl 2.4.5, or excessive foundation settlement may occur due to loading on the foundation. As it will be recalled, under cl 2.4.5 determination of bearing capacity is to consider the weakest state of the foundation under normal site conditions. The whole of section 3 does not apply to class 'P' site, and so the prescribed dimensions for strip footings does not apply.
6. It is submitted that Mr Horsham correctly adopted the bearing capacity of 100 kPa for the purpose of his design works, consistent with cl 2.4.5(a). The defendant says that Mr Horsham's admittedly "limited weight calculation" given in evidence which, it is argued, seemed to bring the weight of the extension well with what could be expected, with all that was required of the hypothetical engineer exercising reasonable care and skill. I record the fact that there is no evidence from Mr Horsham that he considered the weakest state of the foundation.
7. As to the existing footings, the defendant recognises that the footings of pre-1996 residences - that being when the Standard was first introduced - were unlikely to comply, but points out the evidence establishes that this does not mean they were necessarily inadequate. The short point of this is that defendant relies on Mr Horsham's inspections of the soil, about the facts of which I have also commented. I would also make the obvious point, as did Mr Holmes in cross-examination, that an excavation to footing depth will only show the soil conditions to that depth and will not reveal what is underneath. As mentioned earlier, there is no evidence about the depth of these holes.
8. In considering the standard of care on the part of a professional, a court may have regard to a reasonable or responsible body of expert opinion, although questions of standard and breach are ultimately a matter for the court to decide. A body of opinion may be treated as reasonable or responsible if it can be shown to have a logical basis. See Rogers v Whitaker [1992] HCA 58; (1992) 175 CLR 479 at 487-489 and Queensland v Masson [2020] HCA 28, 94 ALJR 785 at [133].
9. In a report dated 16 April 2018, Mr Holmes noted it was apparent from the plans that some significant load points were to be applied to the original footings. The drawings note "Retain existing ceilings - floor joists and place new floor joists parallel to the existing". Mr Holmes says that this indicated there would be a significant increase in the loads applied to the existing footings, especially when account is taken of the new roof and wall framing and cladding, double glazed windows and doors, together with extensive tiling and a large bath. Mr Holmes also referred to a note on Mr Tilley's plans to the effect that he could not guarantee the accuracy of the rooms or existing window sizes due to him not being able to get on the site to take measurements, and that he had done the best of his ability to scale off existing plans. Mr Holmes's view is that this should have flagged the need for careful site investigation into the existing floor framework, to ensure loads were transferred directly to footings, and check to ensure that they had the capacity to carry the load.
10. He returned to this theme in a subsequent report on 22 October 2022. He again noted that the Tilley plans did not contain any details of the existing strip footing system. They had not been specified on the original house drawings nor on the 2013 drawings, so the capacity of the existing footing system was unknown except to the extent of the pad footings on the original plans, the dimensions of which would now comply with the Standard for classes 'A' and 'S' but not for a class 'M' site. He continued:

"Since the design intent was to change the existing loading pattern, and increase loads applied to existing and strip pad footings, as well as applying concentrated loads to new strip and pad footings, investigation and evidence of the adequacy of the existing strip & pad footings, and of the soil profile, to carry such loads, was essential."

1. The plaintiff also called Dennis Florent, a building surveyor. He has been in that occupation since 2011, before which he was a builder, a building inspector, a construction manager and energy assessor. In a report dated 7 September 2020, Mr Florent said that he had reviewed all the documentation which included the Tilley drawings that were certified in 2013, the Form 55 certificate of final inspection and various permits issued by the council. From that, he said that it appeared the defendant provided structural assessment based on an assumed site classification without further investigation of soil bearing capacities and soil horizons.
2. In Mr Florent's opinion, it follows that without initial investigation of the original footing size and construction in conjunction with further soil investigation, it would be inconclusive to assess the existing footings as suitable, particularly in light of the increased overall distributed and applied point loads resulting from the alterations and additions. He added that investigation and determination of the construction of the existing footings would be necessary during the design phase to fully enable determination of their suitability for the proposed design load.
3. In cross-examination it was put to Mr Florent that in the case of designing and certifying an extension such as that which occurred in this case, the assessment is for the extension and not one in respect of the construction of the original house. Mr Florent said that was not necessarily the case; if the existing building was being modified, such as by way of increased loading by an addition on top of it, the whole of the building had to be considered.
4. As to the soil profile, in cross-examination Mr Holmes was asked about the application of cl 2.2.2.(b). He agreed the existing building could be properly treated as a building in the neighbourhood within the meaning of the clause and that the performance of the building could be used as a guide to future performance_._ However, he said, "... but that is totally governed by what you are about to do with that building", adding that there would need to be a thorough inspection including exposing soils and soil sampling. Mr Holmes agreed with the commentary to the clause which says the simplest method based on the history of performance should not be underrated. But he qualified the proposition that examining the history of performance is an appropriate methodology, by saying "Again, I come back to what you are about to do to the building".
5. Apart from what might be inferred from Mr Horsham's evidence, no witness who was called expressed a contrary view to those of the plaintiff's experts. There is no rational reason to reject it. At least as far as inspections are concerned, to an extent this evidence is confirmed by some evidence Mr Horsham gave. When describing his inspection of the house in October 2012, he said that he was looking at the brick veneer structure as being relevant to him because "you're concerning yourself with the weight of the building and also what's carrying the load." Further, in the passage set out above that related to his conversation with the plaintiff on the first visit, he says he spoke about the need to consider contingencies because, until he actually saw the foundations, he had to assume that they may need some work.
6. The following is contained in the plaintiff's written submissions in closing. I agree with this analysis of the evidence.

(a) Mr. Horsham knew from the outset of the works that the architect designed the upper storey extension apparently knowing nothing about the dimensions of the building's existing footings.

(b) He knew or ought to have known that the upper storey addition would substantially increase the weight of the structure and resulting loadings on the existing footings. Whilst he challenges the proposition that the renovations added substantial additional weight, he could produce no evidence to establish he ever really addressed that question. He says he did some calculations but it is plain that if he did, those were superficially limited to only an unspecified part of the additional structure.

(c) He knew (to at least within a year or two) the age of the building and hence the age of those existing footings, and hence the obvious fact the footings would not have been designed with regard to the relevant standard that applied to design and construction of the alterations in 2013 (that is, AS 2870).

(d) He must be taken to have known that there was at least a good chance that the design and construction of those existing footings would not have been to dimensions that would meet the standards imposed by AS 2870, for a building constructed in 2013 to the original 1983 design, assuming his assessment of the classification under that standard as 'Class M' to be correct.

(e) He must be taken to have known that there was at least a good chance that the design and construction of those existing footings would not have been to dimensions that would meet the standards imposed by AS 2870, for a building constructed from scratch in 2013 to Mr. Tilley's design, with the new upper storey, assuming Mr. Horsham's assessment of the site classification under that standard as 'Class M' to be correct."

1. Questions of footing investigations, soil investigations and consideration of the load to be applied, overlap. It will be recalled that the plans as certified by Mr Horsham were submitted to the council in February 2013. The Form 55 completed by him that month noted a request to inspect among other things, "footing preparation". It is clear he had in mind the need for additional works; he said as much to Mr McDougall. In my view, the investigation of existing footings was inadequate. This is a large, generally rectangular building of considerable length. The one footing that might have revealed any information about the strip footing and soil conditions is quite a long way from the southern end of the building. That is where ultimately some shallower footings were discovered and where the area of greater subsidence is. There was no impediment of any significance to having the builder dig holes to uncover the footings at that end of the building, or indeed any point on the south-eastern or western sides.
2. Allied to that, I do not think an obligation to carry out extensive geotechnical assessments as were later done, could then be reasonably imposed, but a limited investigative exercise at a few points around the perimeter ought reasonably to have been done. For instance, during his site inspections in September 2021, Mr Holmes used a basic manual tool of 12 mm diameter called a "Mighty Probe" to assess soil conditions at numerous points around the perimeter. At that time at least, he was able to push it to its full depth of about 1100 mm with minimal effort and withdrawing it caused a sucking noise, consistent with a saturated clay subgrade. No doubt such a mechanism was available in 2012.
3. Further, in this respect, Mr Holmes referred to the geological atlas issued by the Department of Mines - most likely the same or similar document as referred to by Mr Horsham - as showing a considerable variation in the geology area of the point on the Channel where the plaintiff's house is located. A site classification of a particular class does not guarantee consistent soils across the whole of the site; the size of the building must be taken into account.
4. I accept the plaintiff's submission that there is a lack of merit in Mr Horsham's persistent reliance on cl 3.1.5 and cl 3.6 for footing design to justify his lack of detailed investigations and consideration of the state of the existing footings and soil in which they were located. That clause is very clearly concerned with footing systems for ground level extensions. This reliance shows a misunderstanding of, or a disregard, for the plain text. To return to an earlier point, it might show that he was purely focused on the design of the new footings.
5. The defendant criticised Mr Holmes's assessments of the additional load to be applied by the upper storey, a matter which is perhaps more relevant to causation. But in this context, I think a consideration of the sort of additional load would be something that the hypothetical structural engineer would carry out. Mr Horsham did not do this in any meaningful way.
6. The foreseeable risk of harm arising from footings failure created by possibly inadequate footings as such, or in possibly adverse soil conditions, and the additional load applied was not insignificant. The risk was one of substance and not fanciful with a real likelihood of significant loss. Ameliorating steps could have been readily taken, and a reasonable person in the same position would have taken precautions to obviate or minimise the risk. The defendant ought to have carried out footings and soil investigations of not unreasonable scope but considerably beyond what was done, and provided advice to the plaintiffs about the need for underpinning.
7. I find that the defendant was in breach of its duty.

1. There is some dispute between the plaintiff and Mr Horsham about some of what follows, but I do not consider it to be of any real consequence. The essential features are the same. The plaintiff said that the first visible crack was in February 2014 inside the front door. Several others then appeared at the end of the upstairs hallway and in the downstairs bathroom. He arranged for a plasterer to patch them up. That patching did not last very long at all; the same cracks reappeared. He then arranged for the builder to come back. Covers were put over some gaps and repainted. Things continued to worsen. In early 2015 the plaintiff contacted Mr Horsham. At that stage the cracking in the house was predominantly in the south-western corner. There was external cracking on the outside of the downstairs bathroom and cracking around the laundry door. Cracking was also appearing at the northern end of the building.
2. In July 2015 Mr Horsham went to the property. There was a relatively large tree in a corner at the south-western end close to the house. Mr Horsham suggested that it be cut down as subsidence was caused by the ground drying out, hence the need to remove the tree. There was discussion about keeping the area stable in terms of moisture content with no major fluctuations. I am satisfied that this included putting water on the general area of the tree once it had gone. The plaintiff removed the tree within a week by cutting it off to ground level. The cracking worsened. There was noticeable movement in floor levels upstairs and downstairs, more noticeably downstairs. The first exterior cracking of any significance emerged in late 2015. There was another meeting with Mr Horsham in 2016/2017 because of the continuing damage. On either version there seems to have been a heated discussion, mainly about the cause of what was happening. In 2017 the plaintiff consulted Mr Holmes. Mr Holmes suggested complete soil testing, the taking of levels and plumbing check for all leaks.
3. The plumbers found a crack in an underground stormwater pipe on the western side of the building. It formed part of a section from the downpipe located on the brickwork which led to a tank[12]. This pipe was of short length less than a metre from the bottom of a downpipe where it joined a charged pipe. No other pipe cracks were found. No other sign of leaking pipes or other source of water was detected. After that piece of pipe was replaced, there was no sign of further leakage of water of inundation. The plaintiff was not aware of any other damage to the catchment system or the charged storm water pipes. Mr Holmes also suggested that an agricultural drain be installed. That was done in April 2018 to try to stabilise the southern end of the house by addressing any drainage problems. That drain was run for a distance of about four metres from the house, starting from the western side across the southern side, and drained over an escarpment on the eastern side.
4. Cracks to the plaster on the inside of the house started in the kitchen on the northern end. A major crack in the ceiling started in October 2023. Before then there was a wall crack, and pantry benches and cupboards out of alignment.

1. In this case, the question of whether the defendant's breach of duty has caused the plaintiff's loss is, as it was argued, answered by reference to the cause of the subsidence and resultant damage. A great deal of time was spent on this issue. As I mentioned in the beginning, there are two opposing views, one taken by Mr Holmes the other by Mr Kingston.[13] The debate is between the loads created by the new upper level, and a now cut down tree together with excessive moisture due to a now fixed leaking pipe and general drainage issues.
2. Before dealing with all that evidence, there is evidence of the state of the soil conditions which, for the sake of completeness I should set out. Mr William Cromer, an environmental engineering and ground water geologist carried out investigations in June/July 2017. There is also evidence from Dr Griffioen in the form of a report following his investigation in April 2024. Neither was called to give evidence. It is agreed that the results of these investigations do not necessarily reflect the ground conditions in 2012/2013. Both men carried out Dynamic Cone Penetrometer (DCP) tests at various locations around the house perimeter but with some concentration on the southern end of the building. The DCP is a device enabling a set weight to be dropped a set distance onto an anvil block attached to a rod. The rod is driven to the ground by a series of hammer blows and the resultant data is used to calculate the penetration and resistance of the soil.
3. At four of his locations (1, 6, 8, and 9) Mr Cromer found very soft to firm soils with an "unconfined compression strength" range of 25-50 kPa, which translated into a bearing strength of less than 50 kPa. Points 1 and 9 were on the southwestern corner. Point 1 is on the southern side of a bedroom which extends out beyond the general line of the house and has a bay window. Point 6 is the other side of the bay window, while point 9 is slightly to the south of point 1. Point 8 is located at about halfway along the building's length on the western side. Additionally, Mr Cromer dug three pits, one on each side of the building at the southern end, A and B, and another, C, at the very north-eastern corner. He found silty clay on the south-western corner which had a higher moisture content than the other two. In his report he expressed the firm view that the variability in the DCP results across the 12 profiles around the house was "real, reliably reflecting variability in soil strength".
4. In broad terms Dr Griffioen duplicated Mr Cromer's tests although he dug two pits one on the south-eastern corner, the other on the south-western corner close to Mr Cromer's (since filled in) pits, and carried out DCP testing at nine locations which were of a similar distribution. He found that the soil strengths at points 1 and 9 had increased significantly since June 2017, although at point 1 there was a little strength increase from 1.4 m to 1.9 m below ground level. Points 6 and 8 had similar profiles to the June 2017 results. As to the moisture content in his pits A and B, that in A had reduced between June 2017 and April 2024, and was approaching similar moisture content to B, although still somewhat higher. That in pit B was effectively the same for the two years. The moisture level in pit C in 2017 was about that of pit B but there does not seem to be a comparison with a 2024 test or his DCP 5 at that location. In 2017 pit A had a different and unusual moisture "trend" to pits B and C, attributed by Dr Griffioen to the leak in the stormwater pipe. The slightly higher moisture content in pit A compared to B in 2024. could be caused by poor site drainage.
5. There is agreement about a basic cause of varying moisture levels, Mr Holmes noted the phenomenon of seasonal movements due to drying and wetting of expansive reactive clays while Mr Kingston also referred to minor differential movements that equate with seasonal variations.
6. The plaintiff's case is expressly, and rightly, put as a circumstantial one. Broadly, it is argued that the footings of the building that existed to 2013 had been sufficient to cope with the loads imposed but were not sufficient to cope with the additional loads created by the renovations.
7. Principally, the plaintiff relies on the following matters.
   • At the time the renovations started the house was about 30 years old, in sound condition with no signs of instability or movement of any significance.
   • The renovations started in March 2013 and were finished in about November of that year. They substantially increased the area and living spaces of the upper level.
   • That part of the renovations, in particular, added considerable weight with consequential redistribution of loads through to the footings to the extent of overloading and exceeding their bearing capacity.
   • It follows that the existing footings were too small for the purposes of the new completed structure. There is some fluctuation in the extent and direction of movement at various locations but overall, the footings had subsided to varying degrees around the building which has manifested itself extensive damage to exterior brickwork, tearing and cracking of interior plaster work and alteration of floor level. This extends into the northern part of the building.
   • There is a temporal and logical connection between the damage and the renovations. The building could cope before the renovations; it could not cope afterwards.
8. Some of these matters require exploration. Mr Holmes explained his view about the additional load imposed by the extended upper level. He first described the previous upstairs attic area. This was a modest living space with limited head room. The original ceiling was lined with lightweight canite as opposed to plaster which was a lot heavier and denser. In the renovation, the height of the windows was increased and the roof line changed dramatically from the steeply slopping dorm/attic space. The new format maintained parts of the western side, but for the large part of the eastern side, a total new roof structure was constructed at a shallow pitch to maximise the amount of glazing that could be installed on the windows facing the east. Insulation was installed which cumulatively amounted to quite a large amount of weight. I note that photographs show, (and my inspection revealed), substantial window glazing across a large part of the eastern side of the upstairs area. Fewer in number but there are also new windows on the western side,
9. Using information from building component sources, the plans and the many photographs that the plaintiff took in the course of the renovations, Mr Holmes was able to make estimates of items such as the plaster weight, the LVL beams which were required for new floor joists and other supports. It is apparent to me that he was conservative in his approach of assessing quantities from the information he had. He did not include the tongue and groove flooring which he described as heavy illustrating that by saying it normally took two men to lift a sheet of it. He did not include in his calculation things such as additional stud framing, cement sheet overlays, components for the flatter roof along the eastern side, cement sheet flooring for the bathroom and toilet area, wall tiling and a 230 mm deep parallel steel flange channel installed over sliding doors downstairs which alone was a relatively heavy piece of steel.
10. On the upper-level floor framing plan, as certified by Mr Horsham and submitted to the council, Mr Holmes identified 12 "landing" or load points which were imposed by the new upper-level structures. These are fairly widely distributed through the structure and include two internal points - one on each side of the building on the southern side - with one on a mid-point on the southern wall. These "point of load concentrations" were described as follows:

"A load from an upper floor can either be transferred to the wall below as a distributed load, i.e. all the joists land on that wall and they each in turn spread the load across the top of a wall. In a situation where you have a supporting beam that supports the joists that either frame into the side of it in the form of a trimmer, or their - or the member is underneath in the form of a bearer with the joists either sitting on it or going over the top of it, the load of all those joists just go into that beam. The beam then is supported at two or more discrete points. If it is a continuous member, it might have one or two intermediate columns. Each of those columns provide what you class as a point load that loads discretely through a column or a double stud onto the floor structure below and into the foundation wall and into the footings, and ultimately - yeah, down to the footing level."

1. These load points were explained in greater detail but there is no need for me to set any of that out. The simple effect of Mr Holmes evidence is that there was a very substantial weight increase in the upper floor which was distributed both within the building itself and around the perimeter and uniformly so, except for the northern end where the upper floor did not extend out over it. I would add that during the view I saw in the upstairs bedroom quite a large bath and a separate shower enclosed by four very large sections of glass partitioning, one of which includes the shower door.
2. The evidence shows that a survey of levels throughout the building was done in 2017, with Mr Kingston doing a further set of levels in 2024. Mr Holmes reviewed the figures from the surveys. He concluded that while soil moisture had an impact, the additional load applied to the original footing system had a far greater impact based on the overall trend as being for the house to sink into the ground. He explained that there had been seasonal fluctuations up and down, but overall the levels indicated that the overall trend was downwards. The building did not come back every year and then gradually drop and then come back. "It goes up a little bit, goes down further, comes back up, goes down further. There is a gradual trend for it to drop in the ground." This was at varying rates across the building and the subsidence was not uniform. What can now be seen is "movement in different directions in different parts of the building."
3. Mr Holmes was asked about whether the fact that the house stood for 30 years without any apparent damage or evidence of movement in the footings, countered the proposition that soil moisture conditions had caused it. He said:

"I believe so. If the original footings had supported the building through 30 years of seasonal fluctuations in moisture, and we have had periods of five or six or seven years of really dry summers, we've had some periods in that time of really wet winters, that house had performed in its original configuration for 30 years to a standard that people were comfortable to live in it and weren't concerned about undue cracking or creaking or movement whatever. So, the footings were performing in a satisfactory manner. So the shrink swell movement of the clay was not adversely affecting the original house structure."

1. The defendant is critical of Mr Holmes's evidence in a number of respects. In the main, they relate to his methodology and calculating the weight of constructions materials, and the lack of assessment of certain items. As stated above, the weight of essential construction items came to three and three quarter tonnes. It is true, as the defendant submits, that no specific weights were attributed to other materials referred to, but I do not think the exercise required precise calculations as to every single component. It is also true that the calculation of extra loads should be that which could be done from the plans and based on experience, but that is more relevant to the question of breach. In any event, the submission proceeds to the point that Mr Holmes calculations are of no, or insufficient, probative value.
2. While Mr Kingston agreed with the location of Mr Holmes's load points, being those identified points taking additional loads by virtue of the extensions. The issue is the extent of additional load. In broad terms, although he had not done any detailed calculations at all to ascertain the weight of what went into the upper storey, Mr Kingston disagreed with the characterisation of the main building components as heavy. For instance, the timber flooring was "not necessarily significantly heavy"; the large double-glazed widows were "a quarter of the weight of brickwork." But he did agree that all internal tiling and fittings, including such things as the bath and shower, would have to be taken into account, and that the house had to carry more weight than what did.
3. In re-examination it emerged that he did not disagree with Mr Holmes's estimate of additional weight, but that the calculations he, Mr Kingston, used for the purpose of assessing on the laundry and bathroom strip footings were inconsistent in that live loads were included whereas Mr Holmes used dead loads. This had not been raised with Mr Holmes and the calculations are not in evidence. Nor is there any explanation of the import of that.
4. Primarily, Mr Kingston said he did not think that the works done at the southern end caused any great load, with the other points not carrying sufficient loads to amount to overloading on the foundations and consequent distress. In broad terms, it is his view that if subsidence was due to the imposition of loads, you would expect to see cracking primarily at the load points with reflected distress upstairs, if excessive settlement was happening. Each load point has different loads; if you are getting settlement at one location, you would expect to see resultant distress at that location. At the south end, where there is significant settlement happening, there is a lot of distress consistent with that settlement, but he did not see that.
5. Mr Holmes disagreed as to the effects of loading. He said that distress can occur in proximity to where a load point exists, not necessarily immediately at that point. As to the southern end, in cross-examination he agreed that there was a fall to the south. When it was suggested that this was not the same as subsidence at the points of load, he said there is subsidence at the points of load, but they do not necessarily correlate directly. If a load was applied to the southern end wall, and clearly the southern end has dropped, there is a correlation. "It's taking the whole wall down with it."
6. The question of distress at each end of the house is of some significance. Staying with the southern end for the moment, Mr Kingston estimated the load on two of Mr Holmes's load points, one on the eastern wall at the bathroom, the other on the south-western wall of the laundry. These were 67 kPa and 50 kPa respectively. He said this was not significant load on the laundry wall. His point is that the southern end is not overloaded, but that is where the worst of the damage is. In my view, that has to be put in the context of the uncontentious fact that although there are seasonal variations, the soil conditions are less than ideal at that end. That the soils are generally much weaker at the southern end was accepted by Kingston: "The soft soils are at the south end of the house." Additionally, there are the dimensions of the footings as established by Dr Griffioen. As Mr Holmes pointed out, if they are representative of the strip footings throughout the building, or I would interpolate, a substantial part of it, they would be too small to carry the load of a modern two storey building.
7. Hr Holmes gave evidence that in 2014 of seeing the large crack in the kitchen referred to earlier. He said it was not in a join that has given way but was a jagged crack that crossed the kitchen, and which has "literally torn the plaster sheet apart." In cross-examination, Mr Holmes agreed that it can be confidently said that the house has been moving since 2014, particularly to the south. As to the crack in the kitchen and whether it could simply be the product of a structure which has suffered distress for several years, he said it is cumulative stress. It was not there in 2022 when there was no evidence of major distress across the kitchen. But there has obviously been movement since so that by 2024 it "has torn the ceiling in the kitchen apart."
8. Mr Holmes agreed the distress to the south has repercussions throughout the structure. Whether the tear in the kitchen could be a reflection not of subsidence but just of the structure suffering from almost a decade of distress to the south, he said the distress in the building is due to subsidence, not some other cause. There has been movement within the kitchen area but there has been ongoing movement throughout the house. That total movement, whether it is purely within the kitchen, or whether it is because the whole southern end of the house is sinking and tearing away from the northern end, the net result is the same; in 2022 there was no evidence of that level of distress and in the period of two years, there have been no extreme climatic conditions. As to why the southern end was failing at a faster rate than the northern end, Mr Holmes said that there was no clear answer, but more recently significant northern end distress is evident. This represents a significant change since his first inspection in 2017.
9. In turn, it was put to Mr Kingston in cross-examination that there was movement across the entirety of the old footings from the eastern side of the building to the west, including an existing footing under the new kitchen floor at the northern end. (The scope of that included a fracture to the external brick wall- not just mortar cracking - outside the sunroom door next to the kitchen extension on the north-western corner, something which Mr Kingston acknowledged he had seen, and which I saw on the view. He asked counsel how he knew it was moving, the answer to which was the tear in the kitchen ceiling along with cracking above the south wall of the sunroom. Mr Kingston said he believed the kitchen ceiling crack was most likely settlement at the northern end of the kitchen, but he did not know what was causing that settlement.
10. Mr Kingston later agreed that there was movement not only in the footings on the south end of the building but "pretty much all around the building", although qualifying his answer by adding that the south end has so much more movement. He then confirmed movement to the footings across the whole structure. He also agreed that in his investigations he had focused almost entirely on the southern end and did so because that was the worst extent of the distress. When asked about the damage away from the south end, it seemed he wanted to confine the discussion to the upper level. In any event, as to the crack or tear across the kitchen ceiling, he said it is a fracture resulting from ceiling deflection consistent with his assessment of movement of floor levels, but said he could not "offer much else". He agreed the fracture could well be caused by increasing settlement towards the north-west of the building.
11. Mr Kingston was asked to confirm that it was his view the renovations had no role to play in the subsidence. He said that was correct, but that this related to the southern end. He was pressed about whether the proposition applied to the whole building. After some difficulty getting him to address the point, he said he believed that if the renovations were ignored completely, the level of subsidence at the southern end, and movement at the northern end, would have occurred in any event.[14] Accordingly, the defendant's position on this, as it was clarified in closing, is that the damage at the northern end relates to footings issues unconnected with the renovations.
12. Turning then to Mr Kingston's stated causes of subsidence at the southern end, first, there is the tree previously in the south-western corner. This was recommended to be cut down in 2015, and it was. To digress slightly, there is no dispute that with reactive clay soils, dryness can cause desiccation with result and loss of bearing capacity. Excessive moisture can change the consistency of the soil so in addition to 'heave' or 'swell' it also gets to a point where it loses bearing capacity.
13. Mr Kingston's evidence was that the diameter of the stump of the tree was 450 mm, and although not round in shape, he measured it across its widest point. That in itself would cause drying of the clays and result in settlement. In his opinion, the former presence of the tree would "probably" have caused relative settlement at the south end of the house. (I note that there appears to be a qualification in his written report, in that the tree would have caused soil drying affects up until it was removed). After some debate by Mr Kingston in cross-examination, he seems to have accepted that the tree had been there for anything up to 18 years.[15]
14. I acknowledge that his evidence added the leaking storm water pipe to the cause of excessive moisture but before I move to that, I will deal with the tree. Mr Holmes did not disagree that soil moisture has some impact but it was, he repeated, the additional load that had a far greater impact, to the extent that the house has been subsiding at various rates across the building. As to the tree, he noted that the removal and the fact that the base of the tree and the root structure was still in place. The reality was, he said, that the building had commenced to move before the tree was removed and had not stopped moving since. (That damage of course extends to the length of the house although less severe at that end and is worsening.) Mr Holmes says that once the tree was cut down and the moisture goes back with things being resolved, there should be a cessation of movement, but the trend was for it to get worse.
15. In relation to the leaking pipe, photographs in Mr Kingston's report show a downpipe at the south-western end of the building adjacent to the portico over the rear entrance. A pipe on the ground heading in a north westerly direction is suggested as the leaking pipe. His understanding was that minor cracks within this pipe were fixed in 2017, water having been escaping into the vicinity. He noted that because it was a charged system a minor crack would result in a continuous leak.
16. After some prevarication, Mr Kingston seemed to have agreed that he might have been speaking about the wrong pipe. Mr McDougall's evidence established that the relevant pipe was a short section of pipe leading from a down pipe on a south-western corner of the bedroom with the bay window on that side. However, nothing turns on this, as it was a cracked pipe nonetheless. It is the consequences that are important. In evidence is an account from a plumbing business dated 7 June 2017. It shows investigations of various drainage systems were carried out, including by the use of CCTV. The relevant entry is:

"A down pipe on the SW side displayed indications of an issue so we performed exploratory which [sic] discovered some minor cracks within the pipe. Water had been escaping that at this point with no signs of nuisance. Repairs have been made as well as replacement of the entire down pipe and connection". [My emphasis]

1. In evidence I accept, Mr McDougall says that there were no other cracked pipes that he was aware of. But there were some other issues said to have result in excessive and problematic moisture near the foundations. Mr. Kingston points to source in the form of a water tank that previously discharged onto the ground with the water likely having flowed "downhill "towards the south end of the house. In evidence is a plumbing invoice dated 24 April 2018 which included work for the agricultural drain mentioned above. There is an entry relating to a "new water tank overflow". The plaintiff's said this related to a second tank installed in 2012 which did not initially have an overflow, but which was remedied in 2018. This second tank was to act as a subsidiary to the first to increase storage capacity. There is no evidence of the frequency or extent of any overflow in the intervening period. Mr Kingston also suggests that runoff from rainfall reaches the house and saturates the soil.
2. I do not overlook the possible cumulative effect, but I do not regard these sources as having any great significance. The house is slightly downhill from a point on the southern side. Using levels of the area that Mr Kingston took, Mr Holmes demonstrated to my satisfaction, with the benefit on my view, that the fall was such that runoff would mostly bypass the south-western corner. Mr McDougall reported that shortly before the trial started, there had been very heavy rain for two days - a Sunday and a Monday - to an extent of 56 ml measured on his property. Photographs taken on the Monday show ponding, while some taken on the Tuesday do not. Mr Holmes says that this indicates the water has soaked into the ground rather than flowed in the direction of the house. He also noted that one of the Griffioen pits, still uncovered, were not full of water.
3. There was also disagreement about the significance of evidence of moisture in the subfloor of an area at the south-western side of the laundry wall - the laundry being on the southern end. Mr Holmes said that the foundations at that point were obviously saturated as would be expected when there was a build-up of (garden) soil against the outside walls. He thought the subfloor otherwise looked "remarkably dry" with no evidence that water had been sitting there in any volume. Mr Kingston disagreed, saying it was evidence of saturation. However, Mr O'Halloran, a structural engineer called by the plaintiff to give evidence about rectification, (see the footnote to par [126]), also gave evidence about his inspection of this area. He said there were clear signs of "legacy moisture" in the soil, it was lower than the outside floor levels so there was a natural tendency for the moisture to gravitate to and to sit there, "which is just a natural phenomenon and quite common, actually, to houses."
4. Leaving these matters for the moment, there is an observation from Mr Holmes that I think is of significance. He pointed out, and I saw this myself, that the downstairs bedroom on the western side of which I have been speaking, has suffered no damage at all, either internally or to the external walls. It was not the subject of any renovation processes. Mr Holmes says it provides a "control" against which the performance of the rest of the building can be judged. It seems to me that if the entirety stems from soil issues such as dryness, or as it is more robustly put soil saturation, then that room would have also suffered. It seems to be more consistent with varying load points imposed by the addition.
5. In terms of a circumstantial case, I venture to set parts of what I said in Langmaid v Dobsons Vegetable Machinery Pty Ltd (above) at [119]-[124] with which Pearce J agreed, and cited in in Brocklands Pty Ltd v Tasmanian Networks Pty Ltd [2020] TASFC 4 per Blow CJ at [39], Estcourt J at [166]-[167]:

"119 'Where circumstantial evidence is relied upon, it is not in general necessary that all reasonable hypotheses consistent with the non-existence of a fact, or inconsistent with its existence, be excluded before the fact can be found'. 'A rational choice between competing hypotheses, informed by a sense of actual persuasion in favour of the choice made, will support a finding, on the balance of probabilities, as to the existence of the fact in issue.' Nguyen v Cosmopolitan Homes (NSW) Pty Ltd [2008] NSWCA 246 per McDougall J (with whom McColl and Bell JJA agreed) at [55].

120 'All that is necessary is that according to the course of common experience the more probable inference from the circumstances ... should be that the injury arose from the defendant's negligence. By more probable is meant no more than upon a balance of probabilities such an inference might reasonably be considered to have some greater degree of likelihood.' Bradshaw v McEwans Pty Ltd (1951) 217 ALR 1 at 5-6.'

121 In Jones v Dunkel [1959] HCA 8; (1959) 101 CLR 298 Dixon CJ at 304 said that an inference must not be drawn where it is but 'a choice among rival conjectures'. There must be '... evidence supporting some positive inference ... and it must be an inference which arises as an affirmative conclusion from the circumstances proved in evidence and one which they establish to the reasonable satisfaction of a judicial mind ... It follows, of course, that 'a court is not authorised to choose between guesses, even on the ground that one guess seems more likely than another or others': ACCC v Metcash Trading Ltd (2011) 198 FCR 297 per Buchanan J at 306 [31]. However, a court is entitled to draw an inference from 'even slim circumstantial facts that exist so long as that goes beyond speculation': Progressive Recycling Pty Ltd v Eversham [2003] NSWCA 268 at [7] per Young CJ in Eq (Ipp JA and Davies AJA agreeing); Condos v Clycut Pty Ltd [2009] NSWCA 200 per McColl JA at [68] (Campbell and Macfarlan JJA agreeing).

123 Evidence of possibility is capable of supporting a probative inference, and expert evidence of possibility may, as circumstantial evidence, alone or in combination with other evidence, establish causation": Seltsam Pty Ltd v McGuiness [2000] NSWCA 29, 49 NSWLR 262 per Spigelman CJ at [89]; McDonald v Girkaid Pty Ltd [2004] NSWCA 297, Aust Torts Reports 81-768, per McColl JA (with whom Beazley JA and Young CJ in Eq agreed) at [104]"

1. As to the facts from which an inference of causation may be drawn, I prefer the evidence of Mr Holmes to that of Mr Kingston. Mr Holmes gave reasoned and responsive answers to questions. To the extent that is necessary because of ss 60 and 79 of the Evidence Act 2000, and to the extent that his evidence is based on things he was told, those things have otherwise been proved. I have already expressed my view about Mr Kingston's manner of giving evidence. His prevarication and unwillingness or inability to answer reasonable questions did not inspire any confidence. [16] Despite that, his opinion and his stated reasons for the subsidence and damage need to assessed on the whole of the evidence. In that exercise, I observe that a not insignificant factor in his explanation for his hypothesis fell by the wayside. The conclusions he drew from the state of the building before the renovations started proved to be without any real basis. His evidence of observations is based on the one visit to the property in April 2024, albeit over two days and involving a comprehensive inspection. But that inspection was at a single point in time, unlike Mr Holmes who has made several site visits since 2017.
2. Mr O'Halloran also spoke about this general issue of factual causation. As I have mentioned, he was not called to provide an opinion on this point, but the cross-examination about the need for, and efficacy, of his solution for rectification led into that issue. There is no principle that suggests I cannot have regard to his evidence. He is a well qualified structural engineer having specialised in underpinning for 30 years. It was put to him that if Mr Holmes's opinion about the cause of settlement was not accepted, but it was accepted that the house was moving due to soil subsidence to the south, then his less extensive and less costly solution that he proposed in August 2017 after his first site visit would be adequate, (as distinct from the much more extensive exercise now out forward.) He replied:

"Oh, it's - it's a complicated one, because we don't know exactly what the footings are like under the house - the internal footings or any - under any load-bearing walls. And we don't know what they originally were, and we don't know exactly how much load's coming down from the extension and how much is to do with - with when the house was a single storey. The footings under the floor were only just capable of coping with the loads, and then the extension was just the last straw."

1. Further questioning gave rise to these responses:
   • he had not undertaken any analysis as to whether or not the footings before the 2013 extensions were adequate for the soil bearing capacity, but he had come to the conclusion he had because he was trying to understand why things had worsened, involved in which were many factors;
   • he thought that both the imposition of loads and the weakness of soils particularly to the south could both be involved;
   • if it was solely subsidence from weak soils at the south, then the building would have moved soon after it was built;
   • when being asked to assume that the cause was soil subsidence to the south, he preferred not to answer the question of whether his initial proposal would resolve the problem, and went on to say that he did not understand the question in the sense that he was looking at it more widely; there were two different aspects - the "squeaky wheel" which was the south-western corner which had "gone crazy", with other areas not being as extreme but although of the same vein with the same symptoms right through;
   • when it was pointed out that he was not there to explain causation, he said that he was trying to tread that fine line because it was an area where arguably he had more experience than any other engineer in the country because he understood these issues more.

1. On the whole of the evidence, I am satisfied that the building is continuing to subside. That subsidence is not uniform and occurs at different rates across the building. On any view the southern end is the most affected. That is capable of explanation by the fact that some footings at that end were found to be quite shallow. This likely operates in conjunction with what seems to be ordinarily lesser bearing capacity at the end. No doubt seasonal moisture variations have an influence. As a starting point, I see this as a broad issue in logic and common sense. That the damage is caused by the overloading of footings not suitable for the purpose presents itself as a far more likely scenario than a tree removed in 2015, a leaking pipe on the corner of the building fixed in 2017 and suggestions of run-off from various sources at the south end. Damage first manifested itself in early 2014 within a few months of the renovations being completed and has been worsening since that time. The building was performing satisfactorily at the start of 2013; within a few months at the end of the renovations, it was not
2. I am not persuaded by Mr Kingston's views. I have already mentioned the factual bases for those views. I did not find his explanations convincing notwithstanding the rather detailed plans and analyses in his report. I am persuaded by the evidence of Mr Holmes. There is also Mr O'Halloran's evidence which I accept. There is no rational basis for its rejection. These opinions are, of course, part of the circumstantial case. Being careful not to simply make a guess that seems more likely than another, or not to merely make a choice between rival conjectures, I am positively satisfied of the inference as to causation suggested by the plaintiff. I find that the cause of the subsidence throughout the building is the additional load transferred to the existing footings by the extension and renovation of the upper level when those fittings were not fit for purpose in all the circumstances. I find the defendant's negligence caused the damage to the building and loss to the plaintiff. There is a remaining matter of causation that relates to the extent of the loss, but I will deal with that when dealing with the quantum of damages.

1. The parties are agreed that the approach to the quantification for damages in a negligence case is that which was outlined by the High Court in Bellgrove v Eldridge [1954] HCA 36; (1954) 90 CLR 613, notwithstanding that was a breach of contract case. The application of the Bellgrove approach to the quantification of damage for tortious damage to property was confirmed by the New South Wales Court of Appeal in Gagner Pty Ltd v Canturi Corporation Pty Ltd [2009] NSWCA 413, 262 ALR 691 at [89] - [107]. The parties are in tacit agreement that in broad conceptual terms the costs of restoration is the appropriate measure of damages, rather than the diminution in house value, although the cost issue is contentious. The plaintiff does not claim, nor has any suggestion been made, that had the deficiencies of the footings been established and remedial action advised at that stage, the plaintiffs would have abandoned the project, in which case damages would fall to be assessed on a completely different basis, that of wasted expenditure: Bevan Investments Limited v Blackhall and Struthers (No 2) [1978] 2 NZLR 97; Brown Falconer Group Pty Ltd v South Parklands Hockey and Tennis Centre Inc [2005] SASC 75, 91 SASR 152.
2. In Bellgrove, a building case, the Court acknowledged that an owner was entitled to have a building which complied with the anticipated outcome of a contract, but the appropriate measure of damages could be the cost of rectification if that was a reasonable course to adopt. That is, the cost of conformity may require works of a wider scope, but the course adopted must be a reasonable one. As stated in Gagner at [95] the application of Bellgrove in negligence cases is a reflection of a very close similarity between the way in which principles operate for a court to assess damages for a breach of contract consisting of or resulting in building work that is not in accordance with the contract, and for a court to assess damages for tortious damage to property. In both situations, it must be reasonable to take remedial action for the cost of that remedial action is allowable as damages. In line with Belgrove, a particular application of the requirement that the restoration be reasonable is that damages in tort, when measured by reference to cost of restoration, are subject to the mode of restoration being one that is reasonable to adopt to make good the consequences of the tort: Gagner at [97].
3. There are two proposals for rectification, one advanced by Mr O'Halloran for the plaintiff, the other by Dennis Reid, a master builder and architectural designer for residences. Mr O'Halloran's plan is much more extensive with a cost accordingly higher. Mr O'Halloran's final and present proposal arose from an inspection in May 2024. His intention would be to use a patent method of underpinning called "Deep Pinning" which provides a direct connection using steel "micro piles " to bedrock for long term support. The work is guaranteed. After consideration of other options arising from earlier visits, his present opinion is there is no practical alternative to dealing with the issues than this present solution. The basics of it are that once access is gained to the flooring, that is removed, the pins are driven down to bedrock. They are cut off, some framing is welded to the tops and a concrete slab poured. As I have mentioned, there are additional costs.
4. Mr Florent has outlined what he described as a general description of what was required; it was not intended to be complete. But he refers to such things as demolition work to remove decking floors and fixtures, demolition works sufficient to enable Mr O'Halloran to access the various parts of the property, reconstruction of those demolished parts and repairing any obvious pre-existing damage from the subsidence or new damage caused during the process.
5. Mr Reid thought that the substantial demolition and rebuilding exercise proposed by Mr Florent and Mr O'Halloran were unreasonable and unnecessary, if not extreme. What Mr Reid proposes is a little unclear from his reports, but some clarification was given in his evidence. The essential features are to demolish an area at the southern end of the house, install new footings with some underpinning of existing pad footings ("subject to engineer's advice") and reconstruct the demolished area while providing for underfloor cross ventilation. Repairs would be carried out to damaged areas in other parts of the house, accepting that there would be some remaining cracks to an extent that Mr Reid seems to think will be within acceptable tolerances. Control joints would exist but at the boundaries between the reconstructed area and the next part of the house.
6. The area of the house the subject of Mr Reid's proposal can be described as follows. I have spoken of the two downstairs bedrooms, one on either side. On the eastern side there is one, now remodelled with a box window instead of a bay window, and the untouched and unaffected one with the bay window on the western side. The area concerned is all of that area to the south of an imaginary line drawn from east to west across the house at the southern end of the bedrooms, and which encompasses such things as a bathroom, laundry and storeroom.
7. In addition to what I have outlined, while Mr Reid proposes to underpin an existing footing, he excludes jacking up to level floors as this could result in cracking of nearby remaining brickwork. This jacking up of the internal floor and wall framing is likely to include an area of the flooring north of the line I have referred to. This is confined to the hallway running longitudinally from the entry door about midway along the western side of the building, to the relevant area at the south. But how far that extends in a northerly direction depends on what is found. This jacking up exercise would require some access to the sub-floor space.

1. There is an issue raised by the defendant's submission that rests on the proposition that the plaintiff is to be put in the same position in which he would have been but for the defendant's negligence. There is no doubt about the principle: Haines v Bendall (1991_)_ [1991] HCA 15; 172 CLR 60; Arsalan v Rixon [2021] HCA 40, 274 CLR 606 at [25]. The defendant argues the application of the principle means that money that would have been spent in 2013 had the problem being identified and advised to the plaintiff does not form part of the plaintiff's loss. There is also the consequential point that he has had the benefit of that money since that time.
2. This issue was briefly raised in opening remarks on behalf of the defendant, and squarely dealt with in its closing submissions. It was not the subject of any direct evidence led or introduced by either party. The plaintiff argues that general principle does not support the defendant's claim. The plaintiff accepts that he is to be compensated for his actual loss and no more, but argues that there is at least an evidentiary burden on a defendant who wishes to say that part of a plaintiff's loss would have happened in any event; in this case it was for the defendant to disentangle from the total cost of rectification, the cost of what would have been required in 2013.
3. The plaintiff also points to difficulties in the assessment process in that there was no evidence on behalf of the defendant as to what Mr Horsham would have recommended to the plaintiffs, with such matters being peculiarly within his knowledge. The plaintiff also complains that as an affirmative defence raised by the defendant going to causation, it is a matter that was not raised on the pleadings as it ought to have been by virtue of Supreme Court Rules 2000, r 251, and in short, as the issue was not pleaded it was not properly raised and should be disregarded.
4. I am not able to accept the plaintiff's arguments as they are contrary to what I see to be established principles. This issue has not uncommonly arisen in relation to similar actions for damages; that is, claims involving breach of contract and/or negligence of architects and structural engineers, which in the main relate to inadequate foundations and footings. The defendant relies on Auburn Municipal Council v ARC Engineering Pty Ltd [1973] 1 NSWLR 513, a footing construction was identified as failing to provide piles in the design. A properly reconstructed building would require piles which, if they had been installed originally because a proper design had been provided, the initial cost to the plaintiff would have been higher.
5. At the trial, the plaintiff conceded that the cost of now erecting the pile footings within the reconstruction costs of the relevant buildings, should not be included in any awarded damages. On appeal, the plaintiff/respondent sought leave to withdraw the concession and have the costs of piling added to the damages awarded. At 522, Moffitt AP said he thought the correct position was that the cost of erecting the piles was not recoverable and leave to withdraw the concession was refused. Hardie JA agreed.
6. Auburn was considered by the New Zealand Court of Appeal in Bevan Investments Limited v Blackhall and Struthers (No 2) (above). It was also a case against a structural engineer. At 108, Richmond P said that in the case of the plaintiff suing an engineer, the plaintiff must establish what their position would have been if the engineer had, in fact, exercised proper care and skill. Where it is shown on the probabilities that the plaintiff would have proceeded on the basis of a properly prepared design at a cost which would have been substantially higher than that for a building erected in accordance with a defective design, the higher cost factor would be automatically taken care of when determining the amount of money required to put the plaintiff in the same position in which he would have been if he had let a contract on a design prepared with proper skill and diligence by the engineer.
7. At 109-110, his Honour made it clear that the onus of proof was on the plaintiff to "establish that if proper care and skill had been exercised, it would have proceeded with erection of a building in accordance with the appropriate plans, and proof to that effect would in turn involve a question as to the probable price of a properly designed building, for that would be relevant to the question of whether [the plaintiff] would have gone ahead with the project, and also to the quantum of any damages." See also Casey J at 129. [Emphasis added]
8. The defendant also relies on De Pasquale Bros Pty Ltd v Cavanagh Biggs & Partners Pty Ltd (above) which involved, at its heart, breach of contractual duty and negligence on the part of a building designer for failing to undertake geotechnical investigations of soil conditions underlying the site of a building it had designed, leading to inadequate foundations in the soil conditions when built in 1986. In an action by the owner of the affected building against the designer, the damage suffered was economic loss, as I noted earlier, and damages for rectification were awarded. At [35] Chesterman J said that had the defendant properly performed its retainer, it would have known of the existence of the conditions requiring additional piles, which would have been installed as an additional part of the construction at extra cost. That item of cost had not been incurred by reason of the defendant's negligence. His Honour continued:

"It is an expenditure that would have occurred had the geotechnical investigation been conducted earlier. There is no evidence of the 1986 cost of the work, which was presumably less than present cost. However, as [the plaintiff] has had the benefit of the money not spent in 1986 there is probably no reason to reduce the amount of the present cost which should be deleted from the cost of rectification for the purpose of assessing damages."

1. It seems that his Honour's approach was taken without argument. The court had the current cost of the construction of the piles but not, as his Honour noted, that for when the building was constructed in 1986.
2. I have already mentioned that in this case there is an implicit acceptance on both sides, that the plaintiffs would not have abandoned the project. If that were the case, the proper measure of the damage suffered would have been the wasted expenditure on getting to the point at which the issue of the footings would have been identified, along with the cost of remediation at that time. In fact, counsel for the plaintiff conceded that the plaintiff would have incurred the cost of any recommended underpinning in 2013. It follows that as a matter of principle, the plaintiff's loss is the present costs of rectification less what the amount that would have been spent on remedial works in 2013. The difficulty is that given the way the case was conducted, there is no evidence of that cost, at least in the sense of evidence being specifically directed to this issue.
3. The defendant's primary position is that the De Pasquale approach be adopted. On this approach, although the defendant would suggest that there is no, or no sufficient, evidence of the cost of what would reasonably have been recommended by way of underpinning and carried out in 2013, it would presumably be less than the present cost, and as the plaintiff have had their use of whatever sum that was, the present cost of underpinning is not allowable. As an alternative approach, the defendant submits the award of damages be confined to the difference between the 2013 and the 2014 costs. Of course, the precise scope of the work required in 2013 has not been identified nor costed.
4. To further both submissions, the present cost of underpinning has to be established as far as possible. The immediate difficulty is that Mr O'Halloran's suggested method, although described as "underpinning", bears no relationship to what the evidence suggests would likely have been done in 2013. Nor does Mr Reid's proposal assist in any direct comparable way because of the very limited scope of underpinning of a strip footing in two specific locations on the south-western corner, as previously discussed.
5. In any event, as to the primary submission Mr Groves submits the underpinning/stabilisation costs of the plaintiff's proposal should not be allowed if the plaintiff's proposed rectification scenario is permitted. He then proceeded to "deconstruct" the O'Halloran quotation and suggests the removal of three items each which contain reference to underpinning, the total of which is $490,050. Of the O'Halloran quotation, that leaves $26,950 for "Jacking and supporting of structure on underpins" which the defendant concedes is allowable on the basis it reflects the additional cost caused by the delay in now doing the underpinning works, "and because the building has in effect moved and that requires correction."
6. The defendant's argument was said to need extending a little further. That is to exclude from an award of damages any sum in respect of external works needed to facilitate the underpinning which would have not been necessary in 2013, but which needed to be done now. Reference was made to six items in Mr Hawkins' assessment all of which appear under a heading describing detachment and demolition of external timber decks to enable the excavation, jacking and underpinning. The total figure excluding GST is $33,154. Further, the disallowance exercise is said to include the removal and reinstatement of soft land scaping and vegetation, and the excavation of garden areas and landscaping to expose external brick courses and sub-floor masonry. Further still, the defendant says that if consultants' fees claimed as part of the total are in fact to be awarded, the percentage amount of the total claim needs to be adjusted to reflect the removal of those items. There was some further argument against the need for a head contractor with consequential superimposed percentages and the like, which I do not need to detail.
7. Having undertaken that exercise, the defendant's submission was that a reasonable alternative to attempting to disentangle present underpinning costs may simply be to adopt Mr Reid's proposal for rectification. It was submitted that as an alternative it simply recognises the strategy as an appropriate award as a way of addressing the question of how to deal with the 2013 underpinning costs as against what is now required. As stated above, the defendant's alternative to the De Pasquale approach is to confine the award of damages to the difference in underpinning costs between those of 2013 and of the present. That of course requires some estimate to be made of the cost of what reasonably would have been done in 2013 and the present costs; with the latter figure having the same problems I have identified.
8. As a matter of general principle, where loss of some sort has been established the law does not permit difficulties of quantifying the loss to defeat the remedy it provides. A court must do the best it can in light of the evidence, but that must be sufficient to justify the approach taken; it cannot make something out of nothing: see for instance RSPCA (Victoria) v Holdsworth [2015] VSCA 243 at [33] citing Fink v Fink [1946] HCA 54; (1946) 74 CLR 127 at 142.
9. As to what may well have been involved in underpinning in 2013, Mr Holmes provided an explanation of the mechanics. He said that at least one remedy would be to excavate next to the existing footings and "undermine" them in order to carry out underpinning. That would involve "going in underneath the footing, down until you reach a more suitable material to found the footing on", the concrete then being poured underneath to bring it up to the underside of the existing footing. An alternative is to "enlarge the footprint" of the footings by extending the sides of the footing, using additional concrete to achieve a larger footprint, and that may extend under the footing itself.
10. As noted by the plaintiff's counsel, the only evidence of any cost comes from Mr Horsham. The relevant passage is set out in [68] above. It will be recalled that this was evidence from Mr Horsham as to what he said to the plaintiff in October 2012, the essence of which was that until he inspected the foundations, it had to be assumed they may need some work. He said that he mentioned a few methods - which I note seem to be consistent with Mr Holmes' evidence - and advised that it was difficult to predict the cost of underpinning. He then offered to the plaintiff a worst case scenario of an extra $100,000.
11. Of course, that is evidence of what Mr Horsham said he said. But it can be taken as reflecting his view. I think it can reasonably be inferred he was not being flippant and that it was not an unrealistic figure. There was no reason for him to give an inaccurate estimate, and good reason to do otherwise.
12. For the plaintiff, Mr Vince suggested that some assistance could be provided by looking at Mr Reid's estimate of the cost of an underpinning in his scope of works. Mr Reid's proposed method also seems to be in line with what Mr Holmes described. An isolated item in Mr Reid's estimate for "concrete peers and footings including some underpinning" is $25,400. (There may be some additional costs because the allowance for demolition of about $48,800 includes "foundation brickwork and footings removal.") The problem is to apply those figures to the strip footings of the house as may have been done in 2013.
13. I think it can reasonably be concluded that in his estimate Mr Horsham contemplated all strip footings, and that is what probably would have been done given what is now known. A very rough estimate and a crude guide, based on expanding the area and method of Mr Reid''s proposed work to all strip footings (excluding external decks etc and the sunroom) and using the plans as a guide, is a present cost of $200,000.[17] That would have to be discounted by CPI and additional building cost increases.
14. Mr Horsham's evidence is the only evidence that bears directly on the issue. The plaintiff bears the onus of establish his true loss, and despite the plaintiff's general criticism of this evidence, I see no alternative but to adopt Mr Horsham's figure. I think it represents the best alternative in order to get closest to the principle to be applied. The plaintiff's loss has to be reduced by the amount that would have paid for underpinning in 2013. The alternatives suggest by the defendant do not involve true comparisons to what work would reasonably have been done in 2013 and are much more imprecise. It is really a question of doing the best that can be done on the evidence. On the evidence of what was ultimately discovered, it is reasonable to adopt the "worst case scenario" figure of $100,000.
15. The next question relates to the use of the money that would have been expended in 2013. In De Pasquale, the current cost of the work which ought to have taken place much earlier was a known amount - $23,000 - although there was no evidence of the 1986 cost, said to be "presumably less than present cost." In taking the approach he did, it can be fairly said Chesterman J approached the issue using a fairly broad brush. The plaintiff in that case was said to have had the benefit of something less than $23,000 for a 14 year period, there then, his Honour found, probably being no reason not to deduct the present cost. In that case, the plaintiff was a company that owned a commercial building being part of a retail/commercial complex. It might be assumed the amount that ought to have been expended was put to use in at least managing the building for its business interests.
16. In the present case, there are competing contingencies with no firm or clear basis in the evidence. The plaintiffs were retired and renovating the house to enjoy that retirement. In evidence, the plaintiff said they had a "fairly loose" budget for the renovations. Arguably, those things might suggest there was no need to borrow heavily or at all. The plaintiffs may have spent all, some or none of the amount that would have been paid out, and conversely, invested all, some or none. There is a range of possibilities, but I think a reduction greater that the cost itself is warranted. The average RBA cash rate from March 2012 to the present- to which I have been effectively forced to go - is 1.935 per cent. Admittedly not the most accurate calculation but applying that rate to the sum of $100,000 on a compound basis from 12 March 2013 to the present gives an amount of $27,065. Doing the best I can in this situation, I will adopt a very broad brush and reduce the plaintiff damages by $120,000.

1. The defendant's criticisms of Mr O'Halloran's method are based on the general proposition that it is an unreasonable approach. The defendant points out that Mr O'Halloran accepted that an option would be to underpin the areas of obvious subsidence, (Mr Reid's proposal). The defendant relied on the Tasmanian Guide to Standard Tolerances (the Guide). That contemplates some floor differentials across broad areas of a house. The witness conceded that a difference in level of some within 40 mm across a 10 metre space was an acceptable tolerance and quite normal.[18]
2. Further criticisms were that Mr O'Halloran said that normally underpinning of the type he suggested would not immediately be adopted, but there would be some progressive activity, and that he was focused on achieving certainty without previous attempts at remediation and to stop all future movement even though it ought to be expected from the footings of the existing house, and to achieve something that would be better than what would be accepted. As to the last point, Mr O'Halloran's evidence was that that sometimes there were differentials in floor levels but that he often achieved better results than could be expected. Notwithstanding that, in reliance on Mr Florent's evidence, the defendant submits that the 'O'Halloran' approach to stabilisation and rectification has no regard to the degree of tolerances recognised by the Guide, or by the Standard.
3. What Mr Florent actually said was that in his reports he had mentioned the categories of cracking with reference to Table C1 in the Standard. He agreed that the table was a fair approach to whether or not something should be cracked and filled, as against being stripped out and redone. But, he said, one needs to take into account the notes to the table. In that table there are Damage categories. Relevantly, the lower range is Categories 0 and 1, respectively described as "Negligible" and "Very slight" cracks of less than 1 mm and which need no repair. Mr Florent said this is cracking that can be expected and monitored, but (on his interpretation) minor cracking can be upgraded to a greater level if there is a lot of it in one area.
4. It is argued that Mr O'Halloran's method will result in rectification for which the defendant is not responsible. They include remedying inadequacy of the original footings, the pour subfloor ventilation (noted by Mr O'Halloran) and removing an inherent susceptibility to differential footings movement. There is also inclusion of two rooms but only so as to avoid a "moisture trap", those rooms being deficient only in the floor ventilation sense. Mr O'Halloran originally said two rooms could be salvaged in a floor ventilation sense because they would retain timber floors but if the slabs were included elsewhere, those rooms would be isolated and became a moisture trap in themselves; he saw no real benefit in leaving those rooms with timber flooring.
5. The defendant also says that Mr O'Halloran made his recommendations based on the soil conditions identified by Mr Cromer in 2017, and which no longer represented the soil conditions as were identified by Dr Griffioen. As to that, I have already set out the differences. To the extent they are significant, there is nothing at all to suggest that Dr Griffioen's findings represent the permanent state of the building site.
6. As to the "windfall" items, the plaintiff says the sub-floor ventilation did not give rise to any issue before 2013 and but for the defendant's negligence that would still be the case. Rectification works must be compliant, and Mr Florent says that if timber floors were replaced, the floor would probably need improved sub-floor ventilation to meet regulatory requirements. Further, in Mr O'Halloran's view there is no general benefit in having timber flooring on floor joists because the cost would be very similar if not cheaper as far as his proposal was concerned. The plaintiff submits that Mr O'Halloran's method may get close to completely level flooring but, as noted above, it may not. If the floors were out of level before the renovations, about which there is no evidence, it is less likely that Mr O'Halloran's work would remedy that.
7. The plaintiff's essential criticism of Mr Reid's alternative proposal is that it is based on the proposition that the house is not still moving and has not done so since 2020. He did, however, acknowledge evidence of movement by way of the ceiling crack in the kitchen. When taken through comparative photographs over the relevant period, he acknowledged some differences as shown from them, but maintained his view he did not think there was any evidence of movement of any significance. He agreed that any crack opening up more recently would be a symptom of movement in the house. A little later in his evidence, when talking about his proposals for the southern end of the house, he repeated his view that the remainder of the house was not moving, apart from the sign of movement being the crack in the kitchen.
8. The plaintiff makes the further point that as established in his evidence, Mr Reid's proposal pre-supposes a firm base for his piers at 2.5 m which should be contrasted with Mr O'Halloran's uncontested findings on 15 October 2021 of very soft soil through the first four to five meters with a sufficient depth for his purposes of 12 metres.[19] The plaintiff argues that underpinning is to be employed as to the solution to fix the defects, particularly given the evidence of ongoing movement, it would be inappropriate to underpin only part of the property. As to this, there is Mr O'Halloran's evidence who said that if unsecured parts of the property were still moving, they would just keep on doing that. Indeed, Mr Horsham himself had said one needs to be careful not to underpin one section of the house, because more damage could be caused than if you underpinned the entirety. Mr Holmes's evidence about the varying rates of movement throughout the house and uneven subsidence is relevant to this discussion.
9. In his report Mr Florent confirmed this view of things by saying that underpinning sections only of the entire structure can and often does result in further differential movement, as the new underpinned areas are then founded on and supported by different bearing capacity foundation material to non-underpinned areas. He explained this in his evidence:

"[T]he problem with underpinning one section of a building and not the other, what you're actually doing is providing support to that section of the building which is being underpinned, it's now getting support on a different foundation with likely different bearing capacities to the rest of the building. So you will now get differential movement again, because the section that you underpin may well be stiffer than the section that you haven't and then you will get new cracking and movement in locations that you probably didn't have up until this point in time."

1. As earlier established, the mode of rectification must be one that is reasonable to adopt to make good the damage. What counts as making good the damage needs to be understood in the context of its purpose. "That purpose is ascertaining what the work is that is necessary to undo the consequences of the tort having been committed. The only interest of the defendant that bears on the question of whether rectification is reasonable is a financial one... .": Gagner at [105].
2. In terms of the approach to the question of reasonableness, I need to look again at Bellgrove. An argument existed as to the reasonable method of remediation, not dissimilar to the one in the present case. Bellgrove concerned defectively built foundations because of significant departure from the specifications, resulting in "grave instability" of the building. The choices were between demolition and re-erection, or piecemeal replacement of the foundations, with expert opinion to the effect that if any underpinning should be decided on, the whole of the foundation should be replaced; any other form of under-pinning was regarded as useless: see 619-620.
3. The trial judge had allowed for the cost of demolition and re-erection. The Court said not only did it think the trial judge's conclusion was justified, but after reading the evidence and considering the submissions, it was satisfied that underpinning by the piecemeal replacement of the foundations "would, at the very best constitute but a doubtful remedy."
4. The Court said, "To give to the respondent the cost of the doubtful remedy would by no means adequately compensate her." Of significance is the Court's observation in response to the argument that if the owner retained the present judgment and it was satisfied, she may or may not demolish the existing house and rebuild, in which case, it was said she would still have a house together with the cost of erecting another one. At 620, their Honours said that "this circumstance is quite immaterial and is but one variation of a feature which so often presents itself in the assessment of damages in cases where they must be assessed once and for all". [My emphasis]
5. Bellgrove was considered in Tabcorp Holdings v Bowen Investments Pty Ltd [2009] HCA 8, 236 CLR 272. At [17], French CJ, Gummow, Heydon Crennan and Kiefel JJ referred to an example given in Bellgrove at 618, of what might be said to be unreasonable. From that example the Court concluded that "the test of 'unreasonableness' is only to be satisfied by fairly exceptional circumstances."
6. There are three cases from intermediate appellate courts not cited by counsel and which provide authoritative guidance as to the reasonableness test. The first is Kirkby v Coote [2006] QCA 61. The appeal was brought in respect of an action for damages in tort for loss caused by the collapse of some inadequate footings of a house. Other footings had not failed. The trial judge found that the residual threat posed by the remaining adequate footings was real; that is, although there was no certainty as to its magnitude there was a risk that movement of the remaining footings would occur in the future in the event of the clay soil becoming saturated. The trial judge concluded the only reasonable way to rectify the defects was to underpin the whole of the house, and not just part of it as the defendant's had contended, or to demolish it and rebuild. It was common ground that underpinning would be more expensive than demolition and reconstruction. The trial judge assessed damages on the latter basis.
7. Keane JA, with whom Williams JA agreed, discussed Bellgrove at some length. At [52], his Honour said that in speaking of the reluctance of the law to confine a plaintiff to a doubtful remedy, the High Court was contrasting the case before it, with one where it is clear that expenditure imposed on the defendant is disproportionate to any benefit to the plaintiff in terms of the vindication of the plaintiff's rights to recover its actual loss from the defendant. Extracts from his Honour's reasons are as follows:

"[52] ... In this case, the damage as recovered by the respondents are not disproportionate to the benefit to the respondents in terms of the respondents' entitlement to have a house structure which will be, as it should have been, free from risk to its stability as far as its foundations are concerned. It is only by this level of expenditure that the respondents can now achieve a structure which is as stable as it would have been had it not been for the negligence of the first appellant.

[53] It should be noted here that the researches of counsel for both sides have been unable to identify any case in which it has been held to be unreasonable for a plaintiff to recover the costs of demolition and reconstruction where the defendant's defective work has affected the stability of a house structure. This suggests that the courts will be slow to characterise as unreasonable the position of a plaintiff who is unwilling to 'live with' the risk of the serious consequences which may result from sub-standard work which affects the stability of a structure. ...

[58] In the present case, one is not concerned with the breach of duty which results only in aesthetic disappointment. The service negligently rendered by the appellants to the respondents has not left the respondents with a 'perfectly serviceable' house. [Such a] house is one which is effectively free of risk of slipping. The respondents' house is a house which is affected by a degree of instability which would not have been present had the first appellant properly discharged his duty.

[59] As the High Court emphasised in ... Bellgrove ... because the respondents' damages are assessed 'once and for all', the law must be astute to ensure that the measure of damages accurately reflects the restoration of the respondents to the position they would have been in had the appellants not failed in their duties. The respondents should recover the amount of damages necessary to enable them to own a house free of risk so far as its stability was concerned." [Emphasis added]

1. The next case is Metricon Homes Pty Ltd v Softle [2016] VSCA 60, 49 VR 746. The principal issue in that case was the test on an application for leave to appeal to the Court of Appeal from a decision of the Victorian Civil and Administrative Tribunal. That Tribunal had dealt with a claim concerning a defective footing system leading to structural damage to a house. The issue of rectification arose in the context of whether leave to appeal should be granted. At [239], Robson AJA, with whom Warren CJ and Tate JA agreed on the issue, noted the Tribunal had adopted the reasons of Keane JA in Kirkby; that is, "risk of future damage need not be such that there is a likely or probable risk of further damage to the structure, but rather it is sufficient to compensate the owner on the basis of demolition and reconstructions where there is a real risk of damage to the structure in the future". [Emphasis added] At [245], Robson AJA concluded that as the Tribunal found there was a real risk that unacceptable damage would happen again in the future, it can be reasonably inferred that the Tribunal "applied the real risk of damage test adopted in Kirkby", which reasoning showed the Tribunal had applied the correct test.
2. The third case is that of Owners SP 92450 v JKN Para 1 Pty Ltd [2023] NSWCA 114 and can be briefly mentioned. This was a case about a building but with non-compliant cladding. An issue was whether the cost of replacement cladding was the appropriate measure of damages, subsumed within which was a question of proof of the absence of alternative solutions. At [74]-[77], Gleeson JA, White and Basten JJA agreeing, referred with apparent approval to those parts of the judgments of Keane JA in Kirkby, and of Robson JA in Metricon which I have identified above. In my view, these cases are significant for the crystallisation of the "real risk of damage" test in the context of the 'once and for all' rule, following on from Bellgrove.
3. The plaintiff's claim for rectification works is about approximately $1.31 million, which includes Mr O'Halloran's quotation of $517,000. The total cost includes Mr Florent's scope of works. He described the list as "generic in nature" due to the need for formal redesign and approvals in line with statutory requirements. In essence the scope encompasses all necessary demolition of external walls and decks, and internal joinery and fixtures, some of which is to enable Mr O'Halloran to gain access for his pinning and slab work. There is also complete restitution and repairs after that slab work is finished, including installation of windows etc, and general repairs and re-painting. There are some additional items to be added, including a contingency for possible damage to the concrete driveway, and escalation costs before the project can continue. There are further costs such as accommodation and storage which arise on either proposal but are substantially greater in the case of the plaintiffs.
4. Mr Reid's proposal is costed by him at about $354,400 which includes a 15 per cent "overhead and profit allowance." Of course, the costings relate to two completely different proposals. The plaintiff called Christopher Hawkins, a quantity surveyor, to comment on the various costings. Mr Hawkins is highly qualified in his field, and I found him to be an impressive and knowledgeable witness. On his analysis, Mr Reid's proposal would more likely be in the order of $487,000. A component of the difference is opposing views about the need for architectural/designer input, as against proceeding on existing drawings. Mr Hawkins says that in his experience, it is unlikely that an architect or a designer would be content simply to work off the earlier plans.
5. Another item is the cost of the head contractor as allowed for by Mr Hawkins, as against "site supervision". Mr Hawkins' view is that for works of this nature he would typically expect to see a head contractor. That person would coordinate Mr O'Halloran and builders and associated trades, with an overview of the entire process and management of issues arising. Having heard from both witnesses, with respect, I prefer the evidence of Mr Hawkins particularly given his high levels of skill in this area.
6. The difference in costings is very substantial and it is on that basis that I return to the primary question of the reasonableness of the methodology. Because of the cost difference I have given this question particularly close consideration relying on the authorities referred to above. I have found that movement in the house is continuing, and I do not accept that movement caused by the renovations is confined to the southern end. Those findings are of weighty import in the present debate. On the basis on the evidence of Mr Holmes, Mr Florent and Mr O'Halloran, all of whose evidence I accept, I am satisfied that Mr Reid's proposal does not represent a satisfactory approach. I do not think that demolition of the southern end, partial underpinning and restitution of that area - along with an uncertain extent of floor jacking to the north of the relevant area - pose any form of reasonable solution.
7. To do what Mr Reid suggests gives rise to a probability that further movement and consequential damage will occur, or at the very least there is a substantial risk of that occurring. Underpinning in one area can, in fact, exacerbate the problem in others. Mr Reid's solution is, in my respectful view, clearly "a doubtful remedy". I am satisfied that it would leave a real risk that the problem would not be rectified and a real risk of further and continuing damage. I am satisfied the plaintiff's proposal is a reasonable one in all of the circumstances.

1. Subject to the reduction for the 2013 underpinning costs, the plaintiff should be awarded the sum of $1,402,800, which is made up of Mr O'Halloran's quotation, Mr Hawkins' estimate of the proposed scope of works and all incidental costs, the contingency amount of $10,000 in respect of potential driveway damage, and a six per cent escalation in costs as outlined by Mr Hawkins. This is an allowance for increased costs in a period of 12 months before the project can be commenced. Before work can commence the relevant personnel have to be contracted and availability issues would arise. Drawings would be required, and necessary approvals would have to be obtained. Mr Hawkins was not cross-examined about this, and I am satisfied the escalation cost is reasonable. Building permit fees of $212 are claimed in accordance with Mr Florent's evidence and I will allow that sum.[20]
2. There are additional costs totalling $35,136, the quantum of which is agreed. Those costs are the costs of accommodation for the plaintiff while the work is being carried out, furniture removal and storage, and onsite storage. In round terms the total to this point is therefore $1,438,150.
3. There are two additional damages claims. The first is for the costs of having the cause of the cracking and subsidence investigated before the action was commenced and apparently not in anticipation of it. The investigations include those done by Mr Holmes, the surveyor, plumbers and Mr Cromer. The total is $20,556.60. Mr McDougall gave evidence about incurring these expenses and was not cross-examined about them. They were not addressed by either party in closing submissions. I would be inclined to allow the sum as claimed as being within the scope of foreseeable loss caused by the defendant's negligence, with no countervailing disentitling considerations. In round terms, the total figure to this point is $1, 458,710.
4. The second claim is for $150,000. This was advanced in the plaintiff's written closing submissions as referable to "the potential of the works taking 12 months." The claim was not addressed by the defendant in closing. The plaintiff relies on Mr. Florent's evidence about the potential duration. That is indeed what Mr Florent said but there is no evidence as to how the sum claimed is arrived at. I would not be inclined to include this sum for that reason. However, as to both claims I will provide an opportunity for the parties to be heard further.
5. Lastly, there is a claim for pre-judgment interest pursuant to s 35A of the Supreme Court Civil Procedure Act 1932. With the plaintiff's acquiescence, Mr Groves asked that if the plaintiff succeeds, I reserve this for further submissions, thus allowing time for the reasons to be considered. Section 35A requires any order for pre-judgment interest be made "when making a judgment requiring the payment of an amount of money." (I assume "when making a judgment" means ordering the entry of judgment.) An order for interest cannot be made after judgment although under the section, interest that is allowed is distinct from the judgment amount and requires a separate order: Dann v Port Sorell Bowls Club Inc (No 2) [2020] TASSC 53 at [60], [62].
6. I will adopt the same course as did Wood J in similar circumstances in Dann v Port Sorell Bowls Club Inc [2020] TASSC 47 at [339]- [340]. So as to accommodate the parties' position, and also to permit the parties to be heard about the items referred to in the preceding paragraph if that is sought, I will simply indicate that, as I am presently minded, the plaintiff is entitled to an award of $1,338,710, being $1,458,710 less the sum of $120,000.

[1] The gallery is an upstairs hallway which runs on the western side from about the centre of the residence due south.

1. [2] 79 Exception: opinion based on specialised knowledge

(1) If a person has specialised knowledge based on the person's training, study or experience, the opinion rule does not apply to evidence of an opinion of that person that is wholly or substantially based on that knowledge.

(1)

[3] "Consultation on engineering design during the development of the building application documentation". "Design footings, timber and steel framing, bracing, lintels and roof modifications."

[4] See the comprehensive discussion by Shanahan CJ in Valleve Holdings Pty Ltd v Shepperd [2025] TASSC 28 at [95]- [131].

[5] A phrase used by Stephen J in Caltex Oil (Australia) Pty Ltd v The Dredge "Willemstad" [1976] HCA 65; (1976) 136 CLR 529 at 576.

[6] Transcript pp 680 line 12 to 682 line14.

[7] Classification based on soil reactivity appears in cl 2.1.2 and includes class 'A' which relates to such things as rock sites with little or no ground movement from moisture changes.

[8] This would be a reference to the commentary on cl 3.1 of the Standard as referred to in [65] above.

[9] This would be a reference to the Standard, clause 2.4.5 set out in par [64] above.

[10] All depictions of and reference to existing footings on Mr Tilley's drawings are noted to be "assumed". There are also notes on his drawings that he had not been able to get on site to take measurements. Those drawings are dated 4 February 2013.

[11] That strip footing was shown to be 350 mm below ground level. Another digging at the equivalent point on the building but on the south-eastern side, showed that the stripe footing was 230 mm deep and 660 wide, with a depth below the ground level of 500 mm.

[12] The house has no major water supply but is dependent on tank water. That comes from storm water roof catchments with two pipes feeding the tank from the house. There was one tank in place in 2010, but in 2012 the plaintiffs put in a second tank for the purpose of taking overflow from the first, and to increase storage capacity. The charged system means that the water level in the pipes, including the downpipes, is at the same level as the water in the tanks to the southern end of the house.

[13] There are also some comments made in evidence made by Michael O'Halloran, a structural engineer called by the plaintiff to give evidence about his method of rectification and its cost, who strayed into this area of debate while dealing with his methodology.

[14] Transcript pp 572 line 8 to 573 line 34.

[15] An assessment of photographs against oral evidence suggests the real possibility of it being there for up to 22 years before it being cut down. He relied on his opinion about previous cracking and repairs to explain why the building showed no significant signs of damage up to 2013. When pressed, he qualified this to the extent that this was a "possibility" and added that he thought the southern end has subsided before then.

[16] One particular example is provided by his answers in cross-examination about differences in levels taken at different times, first by a surveyor in May 2017 and then by him in 2024. The particular focus was the floor levels across the doorway on the eastern side which had sliding doors fitted. The surveyor's level showed a fall away from the northern end of 8 mm while Mr Kingston's showed a fall in the opposite direction of +16 mm. Despite extensive questioning an answer to the simple question of whether the combined figure of the two measurements represented the net movement of the floor at that point was not forthcoming. See transcript pp 550-551, 594-600.

[17] That is reached by doubling the cost of $25,000 for the designated area at the south to extend it to the western side and multiplying by four to reflect the greater house area as derived from the plans.

[18] Mr O'Halloran said, "... if it's over a very short distance it is a severe outer level. And most places I look at have got that, that's why we are here. So at the end of the day, to be satisfied with something that's that far out as a solution is not really acceptable, especially if it could move more in the future, which it has shown [it] has done now."

[19] Mr O'Halloran's report says, "It was determined that there was approved bearing strata at 14 metres. This was a judgment call made based upon what was found at 12 metres but in my experience, the installation set witnessed at 12 metres would have been adequate to support the underpins in any event."

[20] Mr Reid disagreed with the need for a permit but said he would defer to the opinion of a building surveyor.