1 The plaintiff sues the defendant for damages in tort and in contract arising out of the failure of a hotmix driveway laid by the defendant at the home of the plaintiff in Deviot on the West Tamar.

2 In December 1979 the defendant's agent, Mr Bennett, gave the plaintiff a written quotation, which he accepted, in the following terms:-

"L N Birch No 1466

Foreshore Road,

Deviot 12.12.79

Prepare, gravel & Hotmix driveway from road to road

(drive in drive out) $2489-00

Fine silica gravel average depth 25mm

Hotmix 25mm thick

Weedkiller area.

Clean growth from existing area

Remove silt & Gravel bottom of driveway."

3 The driveway in question is in the form of an inverted "U". The house it serves lies due west of the Deviot Foreshore Road overlooking the River Tamar and the base of the "U" extends along the front or eastern side of the house. The two arms which reach up to the Foreshore Road run parallel to the northern and southern sidelines of the block.

4 The plaintiff purchased the land and cleared it before commencing to build on it. Approximately six months before the quotation mentioned above he marked out the driveway with pegs and cord and brought in many truckloads of road gravel which he spread out with a tractor and blade. He gave evidence that over that period of time considerable traffic aided the process of compaction and that by December 1979 he was satisfied that it was sufficiently deep and compact for surfacing with asphalt. The plaintiff had also by this stage erected concrete kerbs around all sections of the driveway and these were five inches deep and one foot wide. His object was to obtain a smooth hotmix surface over the driveway level with the concrete kerbs.

5 The defendant's employees attended the plaintiff's property about the end of 1979 for the purpose of applying the fine silica gravel mentioned in the quotation. I find that they shovelled up some fine wash which had accumulated at the bottom of the northern section of the driveway, removed a small amount of vegetation growing on top of the existing pavement prepared by the plaintiff, filled some ruts and watered and rolled the gravel. On or about the 30th January 1980 they returned to apply the hotmix. The majority was applied by machine, the gauge of which was adjusted to deposit 25 millimetres of hotmix onto the three sections of the driveway while the balance was applied manually as the machine was not capable of reaching every section of the driveway described by the existing concrete kerbs. Although to the practised eye a difference is visible in the two methods of application, I am satisfied that no criticism can fairly be made of the defendant for using both methods and that the manual sections blended in as well as might reasonably be expected with those where the hotmix was applied mechanically. By the end of the day the work had been completed and I find that the plaintiff expressed himself pleased with the result.

6 The defendant rendered its account almost immediately and the plaintiff paid it on the 5th February 1980. A few days thereafter however he observed a crack in the asphalt surface on the northern section of the driveway about one third of the way in from the front boundary. He contacted the defendant and it was arranged that Messrs Chugg and Midson, both directors of the defendant company who had worked on preparing and laying the asphalt surface, should call on the 21st February 1980. Both were called as witnesses and I accept their evidence that on that day the plaintiff pointed out only one crack in the driveway surface. I also accept their evidence that the crack pointed out extended through the hotmix and down through the pavement or sub-grade to a depth of about 10 inches, that a section of hotmix was broken off and examined by all three and that although it was not subjected to precise measurement all agreed on inspecting it that it was of adequate thickness. Mr Chugg would not accept responsibility for the cracking but did volunteer to fuse it without cost to the plaintiff. I find that the sample was replaced by Mr Midson using tar provided by the plaintiff.

7 Before the crack was fused as promised and within a few days of the inspection the plaintiff observed further cracks appearing. Most were in the northern section of the driveway but there were some in the southern section as well. I find that within one month of the laying of the hotmix approximately six cracks had appeared in the northern section and a smaller number was visible in the southern section. Despite reminders from the plaintiff the defendant did not return to fuse the original crack. Cracking continued in the following two years and a writ for damages was issued on the 23rd February 1982.

8 By about August 1982 a large number of cracks had appeared in both northern and southern sections of the driveway, but none ever appeared in the eastern section in front of the house. The worst section of cracking was in the first third of the northern section of driveway close to the Deviot Road. In September 1982 Mr Chugg cut out four samples of hotmix in areas near the worst cracking. Two of the samples were taken from the northern drive, one about 1½ metres from the front gate post and the second about halfway down the northern arm of the driveway, while the others were taken from the southern driveway a little less than six metres and a little more than 12 metres respectively from the front gate post on the latter section. The thickness of the samples was 30 millimetres, 28 millimetres, 25 millimetres and 22 millimetres. By 1982 there was considerable settlement of the asphalt from the concrete kerbs. Mr Chugg revisited the scene in 1985 and found that considerably more cracks had appeared in both northern and southern sections of the driveway, while the settlement of asphalt from the kerb had also advanced. He also observed and I find having myself conducted a view at the request of the parties, that there were several places where cracks in the asphalt continued into the concrete kerb. The plaintiff claims that the cracks are the responsibility of the defendant company. In opening learned counsel for the plaintiff said that it was his client's contention that the reason for the cracking was the provision by the defendant of a combination of the wrong type of mixture of asphalt and an inadequate thickness of it. The defendant's contention on the other hand is that it supplied an asphalt surface of adequate depth in accordance with its quote and that any settling and cracking in the surface is due to cracking or movement in the sub-grade prepared by the plaintiff himself. Having had the benefit of the expert evidence of the two engineers called by the parties, I have reached the conclusion that the cause of the cracking has not been shown to lie in any inadequacy of the asphalt surface prepared by the defendant. In my view it is due to the instability of the pavement prepared by the plaintiff.

9 It is clear that the proper preparation of the sub-grade is vital to the stability and integrity of a hotmix surface. The plaintiff did not remove any top soil before endeavouring to establish a proper pavement. Both experts agreed that to start building a road sub-grade without removing the top soil was not good practice. Furthermore, the plaintiff's expert expressed the opinion that the sub-grade should have had a minimum thickness of 150 millimetres "and probably up to 200 millimetres depending on how the sub-grade tested". The plaintiff did not claim that it had a greater thickness than 6 inches (or approximately 150 millimetres) and, of the two tests for sub-grade thickness conducted by his expert, one in the northern section showed a depth of only 125 millimetres. The evidence strongly suggests to me that the sub-grade was not of the thickness which an engineer would regard as satisfactory. I think there is support for this in the fact that the asphalt subsided from the concrete kerbs in so many places. The plaintiff's expert was prepared to concede that in those areas of the driveway where subsidence was in evidence there could have been some movement of the sub-grade. However, generally he regarded the absence of wheel rutting and other depressions on other parts of the asphalt surface as indicating that the sub-grade was likely to be satisfactory in those areas. The plaintiff's expert was also prepared to concede that if some cracks in the asphalt lined up with a crack in the kerb that was suggestive that the probable cause was movement in the pavement or sub-grade. He would not concede that it was a more probable cause than not.

10 Although counsel for the plaintiff had in his opening relied on the provision by the defendant of the wrong kind of mixture of asphalt, it soon emerged that his expert did not when pressed assert that the "footpath mix" (which uses a smaller aggregate than the road mix) was inappropriate to the plaintiff's driveway. It is clear that the mix used is in fact widely used for subdivisional driveways. What the plaintiff's engineer, Mr Tabart, relied on was the alleged inadequacy of the thickness of the mixture. He claimed that a minimum thickness of 25 millimetres was required. Mr Bullock, the engineer called by the defendant contended that a thickness of approximately 20 millimetres would have been adequate for this type of mix (assuming of course the stability of the sub-grade). I am not persuaded that Mr Tabart's view should be preferred to that of Mr Bullock whose evidence I found more impressive in any event. However, I am also not persuaded that Mr Tabart's investigations reliably establish that the hotmix surface was to any significant degree inadequate in terms of thickness or to that degree failed to comply with the thickness of 25 millimetres called for by the contract.

11 Mr Tabart took two samples of asphalt when he was first called in by the plaintiff to advise him. He said he actually measured both samples as having a thickness of 10 millimetres. A month or so before the hearing he conducted a series of probes on a gridded pattern throughout the northern and southern arms of the driveway (unfortunately no tests were done on the eastern section which has shown no signs of cracking). He determined that of the 64 test holes 52 showed a thickness of less than 25 millimetres, 21 of these being less than 20 millimetres and four of the 21 being less than 15 millimetres (namely 10, 14, 13 and 14 millimetres respectively). The four samples taken by Mr Chugg were however measured as I have said as 30, 28, 25 and 22 millimetres, while that observed on the 21st February 1980 at the site of the only then visible crack was accepted by the defendant's directors and the plaintiff as adequate. I find that it was adequate, that is of approximately 25 millimetres and that the plaintiff accepted that it was. Generally on questions of credibility I record that I prefer the evidence of the defendant's witnesses to that of the plaintiff. There were a number of matters on which he was quite clearly wrong (eg he asserted that there was no debris present and then carted away from the site on the occasion of the defendant's first day of work, notwithstanding that the quotation clearly called for this to be done). He has a severe hearing problem and is elderly. I do not consider that he was trying to mislead the court but I found his evidence in several areas unreliable.

12 Mr Bullock also made visual examinations of the depth of the hotmix surface. He estimated a thickness of 30 millimetres at the site of the worst crack and 20-25 millimetres at four other points where the thickness could be observed. It is true that he did not use a measure, but I accept that he is of sufficient experience to make a reliable estimate. Mr Tabart's assessment of the thickness (apart from the two original sites measuring 10 millimetres) was based on a procedure of driving a bridge spike through the asphalt and probing with a wire in the 6-10 millimetres diameter circle created by the spike. Such a procedure can only give rough guidance. The length of wire probe to be inserted is governed by the diameter of the spike and in driving the nail through the asphalt the chances of its dislodging a piece of aggregate are not inconsiderable. Mr Bullock said this:-

"Q Well the hotmix in Mr Birch's drive at present is 7 millimetres so you're suggesting then it's a variance of say 7 millimetres?

A I think that you'd be very lucky to measure anything more accurate than that because you would be actually removing that much. A little cone of hotmix from beneath the hotmix."

In my view Mr Tabart's findings are suspect. There may be odd areas where the thickness of pavement is less than 20 millimetres (eg the two sites measured by him as being 10 millimetres), but they are very few and it has not been shown that there is any significant correspondence between the actual crack and the thinness of the mix thereabouts. I am satisfied that the machine was calibrated to deposit the required thickness on the prepared surface and that apart from some elevations and depressions therein which caused variations in depth when the mix was rolled smooth a reasonably even coating of hotmix was deposited. Thereafter rolling produced a further, though no doubt minor, degree of compaction in the thickness of the hotmix. The evidence does not suggest that in the sections laid by hand there was any significant variation in either thickness or susceptibility to cracking.

13 In my view the plaintiff has failed to establish that any breach of contract or negligence on the part of the defendant led to the failure of the driveway. On the contrary, the cause of its failure seems to be movement in the sub-grade which was not properly prepared. I do not consider that the absence of obvious cracking in the house or surrounding lawns militates against the finding that the sub-grade of the driveway shifted in some areas precipitating cracking which compounded the problem by damaging the general integrity of the whole surface which was thereby rendered no longer impervious.

14 The plaintiff claims that the evidence shows the defendant failed to provide what it bargained to give, namely a 25 millimetres thickness of hotmix, and that he is entitled to damages which will enable him to procure that thickness. I do not accept that the evidence does show a general failure to provide this thickness. For the reasons which I have given I do not accept Mr Tabart's probing tests as sufficiently accurate to demonstrate that fact. I find only that in a couple of spots the thickness was as little as 10 millimetres and in some areas may have been 20-25 millimetres thick. I do not accept the submission that in a case such as this, if there is any isolated failure to provide the bargained thickness, the plaintiff is entitled to damages, notwithstanding that no physical injury or damage results therefrom. No doubt there is a remedy if there is a substantial non-compliance with the terms of the contract, even if no damage results. But this could not be regarded as a substantial failure to provide the bargained thickness.

15 It is unfortunate that the plaintiff has incurred the cost of putting hotmix on an inadequate sub-grade and been left with such a poor result. I feel unable to accept the submissions that the defendant was in breach of its duty to him for failing to ensure that the sub-grade was adequate. There is nothing in the evidence which enables me to find that the plaintiff sought to place reliance on the defendant in this regard. He was satisfied in his own mind that the sub-grade was adequate. He had completed the kerbs and made it clear that all he required was the application of materials in fact provided by the defendant. I do not accept his evidence that he asked Mr Bennett if he guaranteed his work and that Mr Bennett replied "All our work is guaranteed". The following passage from his cross-examination shows his attitude:-

Q All you asked Blacktac to do was to make the driveway; prepare it ready to put down the hotmix and put the hotmix down. That's really what you asked them to do didn't you?

A Yes.

Q You weren't relying upon them in relation to the strength of the base that you had prepared were you?

A I would believe it was all right, yes.

Q You weren't relying on them. You told them it was alright didn't you?

A He said it was alright when I told him what I had done.

Q But you told him it was alright too didn't you?

A Yes and he agreed."

I accept Mr Bennett's evidence that the plaintiff told him he had laid the base and that it was up to six to eight inches thick. With the wisdom of hindsight it might be said that it was a pity that Mr Bennett did not quiz the plaintiff as to the mode of construction and impress upon him that the efficiency of the hotmix surface would be dependent upon the stability of the sub-grade. But the plaintiff impresses as a man of decided views and it is hardly surprising that confronted by such a man, with an apparently well prepared sub-grade already surrounded by completed concrete kerbs, who volunteered that the sub-grade was six to eight inches deep and who was asking for a quotation to apply the final coats of fine silica gravel and hotmix, Mr Bennett should have understood the plaintiff to be seeking merely a quote for that part of the project and not to be seeking advice about the adequacy of the plaintiff's own work. The preparation of the sub-grade was not a part of the defendant's contract and any unfitness of the hotmix for the purpose contemplated by the parties is not the result of any breach of its obligations by the defendant.