Christensen v Austin

Texts Cited: Annotated Trees (Dispute Between Neighbours) Act 2006, 2013
Safe Work Australia, Guide to Managing Risks of Tree Trimming and Removal Work, 2016

Category: Principal judgment

Parties: Mark Christensen (First Applicant)
Motoko Christensen (Second Applicant)
David Austin (First Respondent)
Katrina Austin (Second Respondent)

Representation: Counsel:
M Christensen (Self-represented) (First Applicant)
M Christensen (Self-represented) (Second Applicant)
D Austin (Self-represented) (First Respondent)
K Austin (Self-represented) (Second Respondent)

File Number(s): 2024/451962

Publication restriction: Nil

Judgment

Background

1. COMMISSIONER: In a raised garden bed in the rear yard of the Austin’s Castlecrag property, a row of trees was growing beside a Besser block wall, which formed part of a side boundary shared with the Christensen’s. The trees comprised seven palms, and two Sweet Viburnums (Viburnum odoratissimum), growing near the Austin’s dwelling. The boundary was oriented north – south.

2. The Christensen's (the applicants) had asked the Austin’s (the respondents) to remove the trees, as they alleged their trunks and roots were cracking and displacing the boundary wall and blocking terracotta sewer and stormwater pipes.

3. The Christensen family had owned the property since the 1950’s, when the dwelling was constructed, and the terracotta pipes were installed. In or around 1967, an inground swimming pool was installed about 2.5 metres (m) from the common boundary. Between approximately 1990 – 2022, the property was occupied by tenants while the applicants resided overseas or in regional NSW.

4. In or around 1996, prior owners of the respondents’ property installed a semi-inground swimming pool parallel with the common boundary wall, that protruded above ground level by about 0.6m. Sometime later, prior owners established the garden and planted the trees between the pool and the wall, which the Austin’s inherited upon their occupation in 2007.

5. The applicants initially notified the respondents of wall damage in 2012. Though the parties intermittently negotiated repair or replacement of the wall since then, their relationship became acrimonious in the interim and they have been unable to find common ground.

6. Consequently, the Christensen's applied to the Court pursuant to s 7 of the Trees (Disputes Between Neighbours) Act 2006 (NSW) (the Trees Act), seeking orders for removal of the trees, replacement or repair of sewer and stormwater pipes, and replacement of the boundary wall, all at the Austin’s expense. The Christensen's also sought compensation for costs incurred for plumbing, root DNA identification, and a timber protective barrier.

7. An alternative pool safety compliant boundary fence proposed by the Austin’s was opposed by the applicants. The Austin’s had agreed to remove the palms but resisted removal of the Sweet Viburnum trees, as they provided privacy near their dwelling.

The jurisdictional framework for the decision

8. With respect to s 7, an owner of land may apply to the Court for an order to remedy, restrain or prevent damage to property on the land, or to prevent injury to any person, as a consequence of a tree to which this Act applies that is situated on adjoining land. Section 7 is satisfied by the facts of the case.

9. The Court’s ability to make orders is limited, at s 10 of the Trees Act.

10. Matters of which Court must be satisfied before making an order:

(1) The Court must not make an order under this Part unless it is satisfied:

(a) that the applicant has made a reasonable effort to reach agreement with the owner of the land on which the tree is situated, and

(b) if the requirement to give notice has not been waived, that the applicant has given notice of the application in accordance with section 8.

(2) The Court must not make an order under this Part unless it is satisfied that the tree concerned:

(a) has caused, is causing, or is likely in the near future to cause, damage to the applicant’s property, or

(b) is likely to cause injury to any person.

11. If the jurisdictional tests at s 10 of the Trees Act are satisfied, the Court can make orders such as those at s 9 to remedy, restrain or prevent damage to property, or to prevent injury to a person, as a consequence of the tree/s.

12. Before determining the nature of any orders made under this Part, the Court is to consider the following matters, set out at s 12 of the Trees Act:

(a) the location of the tree concerned in relation to the boundary of the land on which the tree is situated and any premises,

(b) whether interference with the tree would, in the absence of section 6 (3), require any consent or other authorisation under the Environmental Planning and Assessment Act 1979 or the Heritage Act 1977 and, if so, whether any such consent or authorisation has been obtained,

(b1) whether interference with the trees would, in the absence of section 25 (t) (Legislative exclusions) of the Native Vegetation Act 2003, require approval under that Act,

(b2) the impact any pruning (including the maintenance of the tree at a certain height, width or shape) would have on the tree,

(b3) any contribution of the tree to privacy, landscaping, garden design, heritage values or protection from the sun, wind, noise, smells or smoke or the amenity of the land on which it is situated,

(c) whether the tree has any historical, cultural, social or scientific value,

(d) any contribution of the tree to the local ecosystem and biodiversity,

(e) any contribution of the tree to the natural landscape and scenic value of the land on which it is situated or the locality concerned,

(f) the intrinsic value of the tree to public amenity,

(g) any impact of the tree on soil stability, the water table or other natural features of the land or locality concerned,

(h) if the applicant alleges that the tree concerned has caused, is causing, or is likely in the near future to cause, damage to the applicant’s property:

(i) anything, other than the tree, that has contributed, or is contributing, to any such damage or likelihood of damage, including any act or omission by the applicant and the impact of any trees owned by the applicant, and

(ii) any steps taken by the applicant or the owner of the land on which the tree is situated to prevent or rectify any such damage,

(i) if the applicant alleges that the tree concerned is likely to cause injury to any person:

(i) anything, other than the tree, that has contributed, or is contributing, to any such likelihood, including any act or omission by the applicant and the impact of any trees owned by the applicant, and

(ii) any steps taken by the applicant or the owner of the land on which the tree is situated to prevent any such injury,

(j) such other matters as the Court considers relevant in the circumstances of the case.

The onsite hearing

13. The onsite hearing allowed inspection of the trees and the fence from both properties. Both parties were self-represented.

14. Thickened trunk bases and roots of the respondents’ palms appeared to have deflected the wall towards the applicants’ land to the extent that the entire Besser block wall, approximately 12m long, required repair or replacement. The Viburnum trees’ trunks were clear of the common boundary wall but the applicants’ photographs and pruning wound locations indicated the prior close proximity of branches beside and above the wall.

The applicants’ proposed orders

15. The Christensen’s proposed the Court make the following orders:

16. Within four weeks of the date of these orders, the respondents are to engage and pay for a suitably qualified AQF Level 3 arborist with all appropriate insurances to remove to ground level trees T1 to T11 which constitute 10 trees within the garden bed adjacent to the wall and one Fig tree in the respondents’ front yard. The work is to be carried out in accordance with the Safe Work Australia, Guide to Managing Risks of Tree Trimming and Removal Work, 2016, with removal of the tree debris via the respondents’ property. The applicants’ pool is to be completely covered by the arborist to prevent tree debris getting into the pool during the removal of the tree.

17. Within four weeks of the date of these orders, the applicants and the respondents are each to obtain a quote from a suitably qualified structural engineer to prepare drawings and specifications for a dividing fence, engage suitable subcontractors and supervise the work required by orders (2) to (12) inclusive. The dividing fence is to be constructed with Besser blocks topped with four courses of Besser majestic screen wall blocks consistent with the existing dividing fence wall. The dividing fence is to meet all relevant standards and is to be located on the position of the existing dividing fence. The dividing fence wall is to be freestanding without contact to a garden bed but with support of a fixed barbeque built in the applicants’ property to the same specification as the existing barbeque subject of the application.

18. Within six weeks of the date of these orders, the respondents are to engage the engineer agreed upon by the parties arising from order (2). If the parties cannot agree on the engineer, they are to select the cheapest quote from order (2).

19. The engineer’s drawings must be obtained by the respondents and a copy provided to the applicants within eight weeks of the date of these orders. The respondents must also obtain a copy of the engineer’s and subcontractors’ relevant insurances and provide copies to the applicants.

20. Within 10 weeks of the date of these orders, the respondents are to apply for development consent for the demolition of the existing dividing fence wall, and construction of a new dividing fence wall as per the engineer’s drawings.

21. Within 10 weeks of the date of these orders, the applicants and respondents are each to approve an itemised quote from a licenced and suitably experienced building contractor with all appropriate insurance for the demolition and rebuilding of the dividing fence wall in accordance with the engineer’s drawings. The quote is to be provided to the applicants and respondents by the supervising structural engineer arising from order (2).

22. Within 11 weeks of the date of these orders, the respondents are to authorise the engineer to engage the building contractor approved by the parties to demolish and rebuild the dividing fence wall along their common boundary in accordance with the engineer’s drawings and to supervise the building contractor and the reconnection of electrical supply and rebuilding of the fixed barbeque constructed from Besser blocks consistent with the extant built in BBQ.

23. Upon completion of the replacement dividing fence wall, the respondents are to authorise the engineer to engage a suitably qualified plumber to replace drains damaged as a consequence of the trees subject of the application.

24. Upon completion of the plumber’s work referred to in order (8), the respondents are to authorise the engineer to engage a suitably qualified tiler to re-tile the surface damaged by trees subject of the application and repair work of the builder and plumber. The applicants are to approve the tile pattern and colour to be used.

25. Upon completion of the work referred to in Order (7), (8), and (9), the respondents are to authorise the engineer to engage a suitably qualified painter to paint the easterly facing side of the wall and all faces of the BBQ consistent with the extant assets subject of the application.

26. Upon completion of orders (1) to (10) inclusive, the respondents are to authorise the engineer to obtain a construction certificate for the works approved under the development consent.

27. The respondents are to pay 100% of each invoice presented by the supervising structural engineer with respect to works required by these orders and to provide the applicants with copies of the invoices and receipted payments within seven days of the date of each document.

28. The respondents are ordered to desist from installing a garden bed in direct contact with the dividing fence wall.

29. The court grant liberty to apply for subsequent orders if required.

30. Within 60 days of the date of these orders, the respondents are to pay the sum of $15,751.50 to the applicants as compensation for plumbing expenses identified in papers lodged with the LEC for case number 24/451962 and incurred by the applicants as a result of blocked pipes in lot 267 and adjacent to the border with lot 266 since 17 March 2010.

31. Within 60 days of the date of these orders, the respondents are to pay the sum of $557.99 to the applicants as compensation for expenses incurred as a result of; (i) erecting a barrier to protect life and property from damage in the event of the dividing fence wall falling and; (ii) plant root DNA testing identified in papers lodged with the LEC for case number 24/451962 and incurred by the applicants.

The applicants’ submissions

16. In the Application Claim Details (Exhibit B), the Christensen’s contended the works proposed in orders (2) to (11) would restore their assets to their existing condition prior to the damage caused by the trees. Order (12) proposed that the respondents pay 100% of the costs of the supervising engineer and the subcontractors.

17. Mr Christensen contended that his findings derived from peer reviewed scholarly reference material and journal articles appropriately substituted for the evidence of engineers or other similar expert witnesses, who were thus not required.

18. Mr Christensen contended that research underpinning the applicants’ statement of evidence had shown that the effective life of a wall constructed with cement masonry units such as Besser blocks was 100 plus years. He noted his wall was approximately 55 years old and therefore would be effective, had the root balls of the respondents’ trees not exerted pressure against the wall. The applicants claimed there was no vegetation on their side, no hydrostatic pressure from their side of the wall, nor downward in-plane pressure that would cause block splitting or crumbling.

19. The applicants submitted the Besser blocks were in good condition but the joining mortar in the bed joints was failing as a consequence of out of plane pressure exerted by the trees. Mr Christensen insisted the Besser block wall was constructed as a dividing fence, not as a retaining wall.

20. The applicants said that plumbers’ ‘camera vision’ showed invasive tree roots that periodically blocked his vitrified clay (terracotta) sewer and stormwater drainage pipes, had entered at the pipes’ joints.

21. Mr Christensen claimed his peer reviewed research indicated that terracotta pipes will last at least 110 years and pipes older than 60 years without tree root invasion were less likely to exhibit blockages than younger pipes. He contended that Fig roots, identified by DNA analysis, had entered the separations in the joints between the pipes, despite prior re-lining of parts of the drainage system.

22. Mr Christensen alleged the roots originated from a Fig tree in the Austin’s front yard. He claimed that compressive forces resulting from expanding trunks and root balls of the trees subject of the application had broken the joints of the sewer and stormwater pipes so that liquids and sewage could not flow freely without seepage.

23. The applicants claimed the barbeque needed like for like replacement as it was integral to wall stability, and electricity to the barbeque and an external power point on the face of the wall would require replacement along with the wall. Mr Christensen also contended that tiles raised as a consequence of compressive force from the Austin’s trees or during pending pipe replacement would require repair and the wall would need painting, all at the Austin’s expense.

24. Finally, the applicants submitted that a supervising structural engineer was required to manage the project and supervise the various works and sub-contractors to ensure compliance with quotes and specifications, due to a breakdown of trust between the parties.

The respondents’ proposed alternative orders

25. In response, the Austin’s proposed the following orders:

26. The joint pool fence shall be replaced within 12 months of the date of the orders.

27. The respondents, at their expense, shall remove palm trees T3 to T9.

28. The respondents shall liaise with Willoughby Council to determine whether the building works are exempt, complying, or require a development application (DA).

29. Should a DA be required for construction of the new joint pool fence, the respondents shall prepare the DA, and the applicants shall provide consent to enable the respondents to lodge the DA. All costs for the preparation and lodgement of the DA, including an engineer if required, shall be shared equally between the parties.

30. The respondents shall provide copies of invoices to the applicants and the applicants shall reimburse the respondents 50% of the cost of each invoice within seven (7) days of receipt of said invoices.

31. The respondents shall engage Willoughby Landscaping and Catlow Remedial Masonry to begin the works.

32. The impacted or damaged tiles shall be removed as part of the building works and the applicants shall replace and repair the tiles at the applicants’ expense.

33. The barbeque shall be removed as part of the building works.

34. The respondents shall work in conjunction with Willoughby Landscaping and Catlow Remedial Masonry to remove the existing joint pool fence and construct a new joint pool fence with a reinforced, solid Besser block base, topped with a wooden fence, 1.8 m high when measured from the respondents’ property.

35. The costs of the new joint pool fence shall be shared equally between the parties.

36. Each party shall pay their share directly to the builder or other relevant contractors in accordance with the payment terms of the builders, engineer, or other tradespeople.

37. If either party fails to make payment to contractor within the required time frame or breaches these orders, the parties may approach the Court in relation to non-compliance to seek further orders.

38. The applicants shall provide all reasonable access via their side path adjacent the common boundary, for the purpose of removal of the trees and the wall debris and building the replacement fence.

The respondents’ submissions

26. The respondents described the wall as a ‘joint pool fence’ and lamented the major cost now required to rectify the wall relative to the much lower cost of repairs required when the parties first discussed the wall in 2012. The Austin’s largely blamed the applicants for the delay, initially because Mr Christensen allegedly breached an agreement in 2013 for the parties to equally share the cost of Madisons Building Maintenance (Madisons) replacing the wall with a timber fence above a new solid Besser block wall base. Mr Christensen had allegedly procured a quote from Madison’s per these specifications.

27. The Austin’s claimed they received no replies to multiple emails sent to the Christensen’s from late 2013-November 2015, and not until the Christensen’s property manager intervened on behalf of the applicants’ tenants, nor response to emails between 2017-2021.

28. The Austin’s contended they had spent the past 13 years trying to resolve the problem in a fair and equitable manner and had provided multiple quotes for works that would have resolved the wall dispute. They gained permission from Council to remove the palms, but with no agreement reached about the replacement fence, did not proceed with the palm removal and the Council permit lapsed.

29. The respondents submitted their proposed fence was just, quick and relatively cost effective as it was unlikely to require a DA and was compliant with all current pool fence regulations.

30. The Austin’s claimed Mr Christensen prevented agreement between the parties by insisting that the new dividing fence must be a ‘like for like’ replacement and include a new barbeque and would not replace the wall unless the respondents also paid for the applicants’ sewer and stormwater pipe repair or replacement and tile path repairs, as a “package deal”.

31. Additionally, the Austin’s challenged Mr Christensen’s expectation that his ‘engineering evidence’ could substitute for evidence and opinion of expert witnesses, regardless of being sourced from peer reviewed scholarly research. In this regard, the respondents noted Mr Christensen’s lack of professional engineering qualifications and or practical experience and alleged that elements of his research results were contradictory.

32. The Austin’s contended the Christensen’s evidence was insufficient to prove their case. They claimed a DNA report which identified roots sampled from the applicants’ pipes as Figs (Ficus sp.) was the only professional evidence submitted by the Christensen’s.

33. The respondents claimed the DNA analysis results consequently proved their trees were not the source of the applicants’ pipe blockage because they had no Fig trees growing on their land.

34. The Austin’s said the subject trees were quite small in 2010, when the applicants claimed that pipe blockages began and this was two years before the initial notice about the wall damage. The respondents noted the applicants’ plumbing receipts since 2010 repeatedly recommended replacing the old terracotta pipes.

35. The respondents submitted the applicants’ pipes had naturally deteriorated over their 60–70-year life and the Besser block wall had similarly naturally deteriorated over its 56 years. They contended that builders who inspected the wall said it was too tall and top heavy.

36. The respondents claimed tile damage was caused by soil erosion from excess water from the Christensen’s pool draining across the tile surface beside the base of the wall.

37. Further, the Austin’s strongly disputed the Christensen’s claims that walls of a garage on the other side of the back yard, built to a similar design with the same materials by the same tradesman at the same time around 1969, were not suffering similar damage as was impacting the common boundary wall.

Findings

38. Firstly, I was not satisfied that the applicants’ evidence may reasonably substitute for the evidence of engineers or other similar expert witnesses. Essentially, Mr Christensen based this claim on his research having been undertaken with scientific rigour using material sourced from peer reviewed “Scopus-indexed scholarly journals”. While many of Mr Christensen’s research-based submissions were well argued and plausible, and may be relevant in the crafting of orders, there were fundamental conflicts and anomalies arising from Mr Christensen’s proposal.

39. Regardless whether they are contracted by applicants or respondents, the key duty of an expert witness is to the Court, to assist with finding relevant facts, free of the influence of either party. To this end, experts are required to acknowledge having read and agreeing to comply with the Expert Witness Code of Conduct in Schedule 7 to the Uniform Civil Procedure Rules 2005 (the rules). Experts reports must align with requirements of the rules. The requirements of expert witnesses under cross examination are dissimilar to those of applicants or respondents.

40. Unlike expert witnesses, applicants carry the onus of proving their case, on the balance of probability under civil jurisdictions. As with legal representatives, they advocate. Applicants select and prioritise evidence to their advantage. Regardless of ethical considerations, parties commonly omit or attempt to minimise the significance of evidence that may disadvantage their case.

41. Therefore, there is a disconnect between the two roles and I am not satisfied that one can ‘wear both hats’ simultaneously without a fundamental conflict of interest. Consequently, I accept the applicants’ evidence as submissions, rather than as a substitute for expert evidence.

The Court may make orders for the trees, the fence, the terra cotta pipes, and for compensation

42. I am satisfied jurisdictional tests within the Trees Act are engaged: at s 7, as the trees are on land adjoining the applicants’ property, and at s 10(1)(a), because the applicants have made a reasonable effort to reach agreement with the respondents, notwithstanding that the Austin’s contested the applicants’ satisfaction of this requirement.

43. In Robson v Leischke (2008) 72 NSWLR 98; [2008] NSWLEC 152 (Robson), Preston CJ explained the ‘reasonable effort’ required to satisfy the Trees Act. At [192], his Honour stated:

“The Trees (Disputes Between Neighbours) Act 2006 does not prescribe any particular means by which an applicant must make a reasonable effort to reach agreement with the tree landowner. The New South Wales Law Reform Commission had recommended in its report a process whereby the affected landowner would write a letter before taking any court action to the tree landowner telling them what problems the tree is causing and asking them to abate the problem and, if the affected landowner has suffered damage, asking the tree landowner to pay the amount needed to compensate for the damage caused: see para 2.45, p 33. Through this mechanism, the affected landowner could negotiate. If the tree landowner did not respond to the notice within the specified time, the affected landowner could then apply to the Local Court for an order: para 2.46, p 33.”

44. At [194]-[195], his Honour said:

“[194] The Trees (Disputes Between Neighbours) Act 2006 does not specify any particular time at which the applicant must make a reasonable effort to reach agreement with the tree landowner, other than fixing the end point by requiring that the Court cannot make an order under the Act unless it is satisfied that the applicant has made a reasonable effort to reach agreement with the tree landowner. Hence, although it would be preferable for an applicant to make a reasonable effort to reach agreement with the tree landowner before making application to the Court, so as to avoid court action, there is no requirement to do so and a reasonable effort to reach agreement can be made after making the application at any time up until the Court determines the application.

[195] The language in s 10(1)(a) of the Trees (Disputes Between Neighbours) Act 2006 that the applicant has made “a reasonable effort to reach agreement” is less demanding than the language used in provisions of other statutory enactments which require parties to make reasonable attempts to reach agreement in relation to matters claimed in the court originating process.”

45. Therefore, the requirement at s 10(1)(a) of the Trees Act to make “a reasonable effort to reach agreement” does not prescribe the conduct of applicants or how applicants negotiate, nor are attempts to compromise necessarily required. Though the respondents did not like the contents or manner of some of Mr Christensen’s proposals, notably his draft ‘deed of agreement’ of July 2022, the respondents’ log of 60 emails from July 2013 to September 2023, contained evidence of the applicants’ reasonable efforts to reach agreement.

46. Section 10(1)(b) of the Trees Act is engaged as the applicants submitted evidence of appropriate service of the application and the orders sought. Further, the Court provided sufficient notice between preliminary directions hearings and the final hearing.

47. Based on my observations on site, the applicants’ submissions, and findings in the respondents’ arborist report, I am also satisfied the trees caused damage to the common Besser block boundary wall, which is property owned by both parties. Therefore, the key test at s 10(2)(a) of the Trees Act is engaged.

48. Consequently, I can make orders for the trees and the section of fence they have damaged, pursuant to s 9 of the Trees Act, as well as for the remainder of the boundary fence, pursuant to s 13A of the Dividing Fences Act (NSW) (Fences Act). Under the circumstances of the case, however, only the masonry wall section of the boundary fence required replacement.

49. The Court may also make orders covering the applicants’ terracotta pipes if, as claimed, roots of the respondents’ trees are proven to have damaged them. Additionally, orders may be made for compensation for past plumbing expenses, to the extent the applicants’ claims are found to be justified, and subject to a 6-year limitation under s 14(1)(d) of the Limitation Act 1969.

Section 12 considerations

50. Before making orders, I have considered the matters set out at s 12 of the Trees Act and raise the following issues:

51. Removal of the palms would ordinarily require a permit from Willoughby Council (Council) under the jurisdiction of the Environmental Planning and Assessment Act 1979. However, the jurisdiction of the Trees Act takes precedence over such Council permission (s 12(b)).

52. The trees provide amenity, not only to the respondents’ property but to the broader landscape. Thus, I have contemplated solutions that would allow the trees to remain, particularly the Viburnum trees which the Austin’s value for privacy (s 12(b3)).

53. However, I accept the applicants’ contention that a new wall/ fence would likely be damaged by retention of the current trees. Additionally, the respondents’ garden soil will need to be cleared from the base of the wall to provide access for construction of a new wall. Therefore, I find no viable alternative other than ordering removal of all 9 trees along with the wall, at the respondents’ expense.

Guidance – Wall dismantling and tree removal

54. Provided relevant contractors employ due care, the wall may be safely dismantled, block by block, initially from the respondents’ property where the upper wall is more accessible. As a contingency for accidental damage, orders made under the Trees Act require contractors to hold appropriate public liability insurances. Due to apparent deterioration of mortar between concrete blocks, it appeared likely that the blocks could be separated relatively easily with a bolster or similar tool. In the process, used mattresses or similar padding may be employed to protect the applicants’ tiles in the event that blocks fell inadvertently. I accept the applicants’ submission that the existing Besser blocks were likely to be sound. This presented an opportunity to recycle the blocks, subject to the opinion of appropriate contractors.

55. The applicants’ fear that during removal, the trees may collapse towards their property and cause damage to their swimming pool, was largely unfounded. One may reasonably expect the palms to have dense, strong, relatively extensive fibrous root systems effectively anchoring them in the surrounding soil. The palms were not very tall, nor thick. Therefore, it should be well within the capacity of Australian Qualification Framework (AQF) Level 3 arborists, to safely climb and dismantle the trees with minimal likelihood of ground-based instability.

56. The orders covering tree removal shall include specifications to minimise the likelihood of damage. Once the trees are reduced to near ground level, the remainder of the wall may be dismantled and stacked or removed. Root balls and soil may then be cleared away from the wall on the respondents’ land and existing foundations accessed for inspection and quoting.

57. The proposal, within the applicants’ order 1, for the pool “to be completely covered by the arborist to prevent tree debris getting into the pool during the removal of the trees” shall not be granted. I am unaware of such precedents within orders under the Trees Act, but liaison with the arborists and scheduling works to avoid windy conditions can assist with minimising debris blowing towards the pool. Ordinarily, normal cleaning and filtration processes are sufficient to remove residue that may enter pools and the applicants may elect to employ additional protective measures.

58. It is conventional for orders for access to be based on the most efficient, least expensive, safe available option. The applicants resisted required works being undertaken from or through their property but the applicants’ side access provided a direct route beside the common boundary to the street frontage. Conversely, the respondents’ access was indirect and restricted, on the far side of their property, which required a much greater distance for transit of debris. Thus, it was more practical and efficient, and would be much less expensive, to remove debris via the applicants’ side access, notwithstanding that any skip bins utilised shall be placed on the Austin’s land if they are prohibited from the road or nature strip. Once the wall is initially dismantled to around the soil level of the Austin’s raised poolside garden, potential danger or damage from wall collapse would largely be mitigated.

59. Therefore, provided the wall and tree removals are undertaken in accordance with the Court’s orders, I am not persuaded of any sound reason to deviate from the Court’s conventional approach of ordering debris removal via the most efficient means, which is the applicants’ side access.

Fence replacement – apportionment of cost

60. Subsequent to initial notification of wall damage in 2012, in an email dated 8 October 2017, Mr Christensen alerted the respondents to provisions and consequences arising under the Fences Act, specifically that retention of the trees allegedly causing wall damage was a ‘negligent act’.

61. Under s 7(1) of the Fences Act, adjoining owners generally contribute equally to “…the carrying out of fencing work in respect of a dividing fence of a standard not greater than the standard for a ‘sufficient dividing fence’.”

62. However, at s 8 of the Fences Act, the adjoining owners’ contribution is not necessarily equal where damage has been caused by acts of the owners, as follows:

Contribution where negligent or deliberate act

(1) Despite section 7, an adjoining owner is liable for up to the whole cost of the fencing work required to restore a dividing fence that has been damaged or destroyed by a negligent or deliberate act of the owner or of a person who has entered the land concerned with the express or implied consent of the owner.

(2) Any such dividing fence is to be restored to a reasonable standard, having regard to its state before the damage or destruction.

(3) In determining an adjoining owner’s liability under this section, it does not matter if the negligent or deliberate act concerned took place before the commencement of this section.

63. Disagreement over the type of replacement fence, and ‘who pays’ were recurring issues that prevented dispute resolution, and each party blamed the other for protracted delays.

64. The respondents’ email log showed the applicants failed to reply to the respondents’ emails for unreasonably long periods; from 2013 – 2015 and from 2017 – 2021. This claim was unchallenged by the applicants.

65. However, the respondents repeatedly denied or minimised the trees’ role in causing wall damage. As recently as 15 December 2022, Mrs Austin claimed the palm trees were exerting “no pressure” on the fence (Respondents’ log - Email 59), notwithstanding that the Austin’s submitted no evidence or claim of having gained advice from an arborist or other expert about the wall damage until recently. Had they gained such advice, the respondents may have removed the trees and arrested the damage much earlier. Nonetheless, due consideration must also be attributed to the impact of Mr Austin being gravely ill for many years during this period.

66. In their submissions, the applicants used the initial notification of 2012 as their reference points for the aging assets while the respondents used 2025. As the adduced evidence indicated responsibility for the disputes’ extended duration sat with both parties, I have used a nominal mid-point around 2018-2019 for consideration of relative impacts of various causes of damage.

67. As I am satisfied the trees are a primary and relatively obvious cause of the wall damage, I concur with the applicants that the retention of the trees for the duration of the dispute may reasonably be considered a ‘negligent act’ under s 8(1) of the Fencing Act. It follows that the respondents are “liable for up to the whole cost of the fencing work required to restore a dividing fence*”*.

68. Notwithstanding this finding, I am not satisfied that the respondents should pay the full cost of the wall proposed by the applicants for the following reasons arising at s 12(h) of the Trees Act, which says:

(h) if the applicant alleges that the tree/s concerned has caused, is causing, or is likely in the near future to cause, damage to the applicant’s property,

(i) (the Court must consider) anything, other than the tree, that has contributed, or is contributing, to any such damage or likelihood of damage, including any act or omission by the applicant and the impact of any trees owned by the applicant.

The applicants’ proposed fence

69. Under the applicants proposed order (2), the “dividing fence is to be constructed with Besser blocks topped with four courses of Besser majestic screen wall blocks consistent with the existing dividing fence wall. The dividing fence is to meet all relevant standards and is to be located on the position of the existing dividing fence. The dividing fence wall is to be freestanding without contact to a garden bed but with support of a fixed BBQ built in the applicants’ property to the same specification as the existing barbeque subject of the application”.

70. As noted at [16], the applicants “contended the requested works proposed in orders (2) to (11) will restore the applicants’ assets to the state that existed before the trees caused the damage”. I disagree, however, not least because the wall was now 56 years old and was about 43 years old when the respondents were initially notified of damage in 2012. Therefore, it was subject to significant age-based deterioration.

71. The Land and Environment Court’s Annotated Trees (Dispute Between Neighbours) Act 2006, 2013 assists users with interpretation of the Trees Act and provides relevant case precedents. It notes age-based deterioration, or ‘wear and tear’ as one of various factors commonly considered under s 12(h), when determining the extent to which a tree or trees may have caused alleged damage. Just as occurs with claims under house contents or car insurance, the value of items is depreciated and financial liability is apportioned between the parties, accordingly.

72. Based on his research, Mr Christiansen contended that this type of Besser block wall would ordinarily remain fit for purpose for 100 years or more, if not for the impact of lateral pressure on the wall caused by the trees.

73. However, the Court regularly deals with the interaction between trees and masonry walls and with many reports from engineers about such walls. With consideration for deterioration of mortar over time and variability of construction methods before the introduction of modern standards, the consistent average safe useful life of concrete block walls reported in such engineering reports is about 50 years. Such old walls were generally of lower quality and poorer design standards relative to current requirements, and this wall fitted that description.

74. Mr Christiansen contended the wall was high-quality and was built in or around July 1969, by an Italian tradesman with significant expertise, with builders labouring assistance from both Mr Christiansen and his brother. However, the applicants submitted no evidence, such as trade qualifications, to support this contention nor to support their claim that the boundary wall was constructed in adherence with any contemporaneous standards or Council requirements.

75. To substantiate his claim that the trees were the solitary cause of the boundary wall damage, Mr Christiansen submitted that Besser block walls of a garage on the opposite side of the yard, which had been constructed at a similar time by the same tradesman, were still in very good condition. Having consulted real estate website photographs which were taken inside the garage, the respondents strongly contested this claim.

76. Upon inspection by the Court, the garage walls displayed deterioration and cracking of mortar between blocks and at junctions with doors and windows, not dissimilar to the boundary wall. While some wall cracking was likely to have related to thickening of conspicuous raised Fig roots on the adjacent lawn, I was nonetheless satisfied that clearly visible crumbling and deteriorated mortar had predisposed the blocks to such cracking.

77. Therefore, while I am satisfied the trees were the primary cause of the wall tilting and cracking, age-based deterioration and strength loss of mortar had also contributed to damage visible on all the block walls.

78. The deterioration appeared to have been exacerbated by the absence of painting or sealing the boundary wall for many years, considered at s 12(h) as the applicants’ ‘failure to maintain their own property’.

79. Adequacy of design is also considered under s 12(h). Though the boundary wall appeared fairly straight and level, its design was clearly inadequate. The respondents orally submitted that various builders opined the wall was ‘top heavy’ and inherently unsafe and this was my initial impression. It appeared disconcertingly tall for a single thickness block wall, with four breeze blocks (1.2 m) and a 50mm cap above 5 courses of standard blocks (1.0m). At about 2.25m high, the wall was about 450mm taller than the typical 1.8m height of a free-standing wall.

80. Additionally, the wall’s pillars were approximately 3m apart, whereas pillar spacing under current construction standards is typically about 1.8m. I was unable to adequately clarify Mr Christiansen’s contention that the pillars were reinforced with concrete but there was no suggestion that the wall contained steel reinforcing, as would likely be required under current standards.

81. Based on the cumulative impact of the unusual height, excessive pillar spacing and relatively inadequate reinforcing, the wall was inherently structurally weaker than a wall compliant with current standards. Additionally, the presence and composition of foundations was unknown.

82. In light of the 50 year safe useful life consistently applied to similar walls by multiple structural engineers, and considering weakness arising from age-based deterioration and the obvious design flaws of the boundary wall, I am not persuaded that Mr Christensen’s safe useful life expectation of 100-years or even approaching 100-years was reasonable for this wall, had the trees not damaged it.

83. In Bentley v Hinchen [2008] NSWLEC 1348 (“Bentley*”*), a case with similar circumstances; at [10]-[13], Moore C, Taylor C, and Fakes AC stated:

“10 The question of the retaining wall as a matter of some greater difficulty. We have two quotations - one of which is based on the replacement of the retaining wall with new materials (it is a quotation of the order of $7,000) and the other is one which recycles the materials at a total cost (including GST) of $2200. Ms Bentley seeks reimbursement of the lower of the quotations.

11 We have looked at the retaining wall and we are satisfied that there are two significant matters that we should have regard to concerning its present condition. The first is that we are satisfied that a deal of the bowing to the retaining wall has been caused by pressure from the roots of the tree or soil settlement arising from the growth of the tree. To that extent, we are satisfied that some order for compensation in this regard should be made for the reconstruction of the wall.

12 However, we have also had regard to the construction methodology used in the retaining wall. In the first instance, the wall has been constructed, we are satisfied, in a fashion which does not represent sound practice as to the depth the retaining posts are embedded in the ground and the orientation used in laying the sleepers for the retaining structure. Further, there is no evidence that there is any appropriate drainage provided behind the retaining wall.

13 As a consequence of those mitigating matters on the potential liability of the Hinchens, we are satisfied that it would be inappropriate to award the entirety of the amount claimed. Doing as best we are able to, we consider that the Hinchens should reimburse Ms Bentley with the sum of $1100, being 50% of the cost of the lower of the quotations, on a similar basis - that is within 60 days of the provision to the Hinchens of a receipted invoice for the carrying out of the work.”

84. Using Bentley; at [10]-[13] as a guide, regardless that the trees were a primary cause of wall damage, it is reasonable to account for the wall’s structural inadequacies and depreciation of the wall’s value over the last 50 years and thus apportion the wall’s replacement cost between the parties.

85. Significantly, masonry walls over a height of 1.2 m ordinarily require DA approval from Council. Due to progressively increased requirements since the wall was constructed, the new masonry wall proposed by the applicants, at the respondents’ expense, would almost certainly require a much higher construction standard than the original wall. This outcome would disproportionately advantage the applicants.

86. In discussing similar circumstances in Yared v Glenhurst Gardens [2002] NSWSC11 (“Yared*”*); at [112], Austin J said:

“However, there is another powerful consideration pointing against my making a mandatory order to compel the defendant to carry out remedial work [on a retaining wall] wholly at its expense. To make a mandatory order in the present case would be to commit the defendant to very substantial expenditure which would disproportionately enrich the plaintiff. The old and substandard wall would, of necessity, be replaced by modern and effective retention works. Although there is no direct evidence on the point, it is plausible to infer that the value of the plaintiff's property would be enhanced by that work, at no cost to her. That consideration, in its context in the present case, would probably have led me to decline specific relief.”

87. Consequently, while current requirements necessarily require construction of a wall of superior quality than the original wall, the Austin's financial contribution shall be based on the characteristics of the original wall.

The respondents’ proposed fence

88. The respondents wanted the boundary fence to simultaneously satisfy Council’s swimming pool safety requirements and retain the poolside garden soil. To this end, the Austin's proposed a 1.8m timber fence above a reinforced Besser block wall, about 0.6m high. To the best of my understanding, such a fence would be an ‘exempt development’ as a DA is not required where the masonry wall base is no higher than 0.9m. Nonetheless, as proposed in the respondents’ order (3), liaison with Council would be necessary to clarify whether the building works are exempt, complying, or require a DA.

89. The respondents argued their proposed wall provided compliance with current pool safety requirements for both parties. However, the applicants’ proposed wall and barbeque resulted in pool safety compliance for neither due to both the barbeque and holes in the breeze blocks provided ease of fence climbing.

90. The applicants currently retained compliance with superseded pool safety requirements that wall replacement would extinguish. Rather than accepting the respondents’ mutually pool safety compliant fence proposal, however, the applicants announced plans to install a separate pool fence a few metres from the boundary wall and retain their proposal to duplicate the original wall.

Wall replacement - Summary

91. As with the Commissioners in Bentley, unravelling multiple considerations impacting the replacement fence was not without difficulty. I was satisfied the trees were the main cause of wall damage, but deterioration due to wear and tear over more than 50 years and the wall’s design and structural inadequacies also contributed to the damage.

92. To provide reasonable consideration of the various damage causes, the respondents shall pay 75% and the applicants shall pay 25% of replacement fence costs, subject to the following criteria.

93. Both replacement fence options satisfied the requirements of a ‘sufficient’ fence under the Fences Act, but the applicants’ preference was likely to be much more expensive, particularly as the respondents’ preferred fence was unlikely to require a DA. Although s 8(2) of the Fences Act says, “Any such dividing fence is to be restored to a reasonable standard, having regard to its state before the damage or destruction”, this does not confer rights upon the applicants to exclusively determine the type of replacement fence.

94. I am not persuaded by the applicants’ claim that the replacement fence cannot also be a pool safety fence nor retain the respondents’ poolside garden, merely because the original wall initially only served as a boundary fence. Mr Christensen based this restriction on the purpose of the original wall but this is irrelevant if, as is likely, the DA requirements for the foundations and base of the applicants’ replacement masonry wall satisfy or exceed the engineering requirements for a wall to retain the respondents’ 0.6m deep garden, and the species used for garden replanting are restricted and prescribed.

95. Mr Christensen essentially supported this conclusion in ‘History’ at lines 7 and 8 of his email of 11 October 2017, where he noted: “The Besser blocks and footing would have been sufficient for (retaining the soil between pool and wall) but the growth of the palm trees has placed too much pressure on the wall and it is now clearly failing” (Respondents’ log Email 24).

96. Nonetheless, as the respondents’ failure to remove the trees was a primary cause of wall damage, it is reasonable for the applicants to gain the initial option to construct their preferred ‘like for like’ Besser block wall.

97. Consistent with determinations in Bentley*;* at [10]-[13], and Yared; at [112], the respondents’ shall contribute 75% of the cheaper quote for a ‘like for like’ wall with concrete reinforced pillars at 3m intervals, constructed with recycled Besser blocks and recycled breeze blocks, and including replacement of the power point, plus 75% of the cheaper quote for a foundation sufficient to retain the respondents’ 0.6m deep garden bed, plus 75% of the cheaper quote for assessment of the existing foundation by a qualified structural engineer, following the foundation’s exposure, and engineering drawings required for the above foundation quote.

98. Each party shall procure and exchange one quote for each of these three components from suitably licenced, insured contractors. The applicants shall organise and pay for the wall’s construction in the first instance. The respondents shall pay the applicants 75% of the cheaper quote by electronic fund transfer (EFT) upon completion of each work component, within 7 days of receipt of a paid itemised invoice from the applicants, for each work component.

99. The respondents shall not be liable for organising or paying for the DA or other Council requirements, or for additional engineering drawings or wall reinforcement, or foundations greater than the foundations required for a 0.6m wall retaining the respondents’ garden.

100. Such costs relate to property improvement for the applicants, not to reasonable compensation for damage to an old wall (Yared; at [112]) and are not representative of costs incurred with the original wall. As the existing wall did not appear to have been painted for many years, no orders shall be made for the respondents to paint the replacement wall.

101. No orders shall be made for the respondents to contribute to barbeque reconstruction costs. Regardless of secondary damage from the trees impacting the wall, the barbeque appeared unused, forgotten, and significantly deteriorated from age-based wear and tear. While the existing barbeque may have been required to compensate for the wall’s structural inadequacies, such an edifice would be unnecessary to buttress a properly constructed reinforced boundary wall built to current construction standards. Particularly considering its derelict condition, I was not persuaded that Mr Christensen’s sentimental attachment to the barbeque justified the respondents paying for a replacement that would constitute property improvement for the applicants. Further, once a new pool fence was installed, a like for like barbeque as currently located would probably restrict access between the two fences.

102. Should the applicants elect not to proceed with a ‘like for like’ Besser block wall, or fail to satisfy time limits in the orders, the option to build the fence shall transfer to the respondents, who shall initially clarify development requirements with Council.

103. Each party shall procure and exchange one quote from suitably licenced, insured contractors for a 1.8m high timber lap and cap paling fence with steel posts concreted into a 0.6m high recycled Besser block retaining wall with sufficient foundations to retain the garden bed, per the engineer’s specifications. In the first instance, the respondents shall engage and pay the contractors to construct the fence.

104. Upon completion of the fence, the applicants shall pay the respondents 25% of the cheaper quote by EFT, within 7 days of receipt of a paid itemised invoice.

105. Prior to re-establishing the poolside garden, the respondents shall install appropriate drainage behind the wall. The applicants shall not be responsible for any contribution to such drainage nor Council fees or other attendant costs.

106. Species in the poolside garden shall be restricted to annual flowers, herbs etc or soft wooded perennials with a maximum height of 1.5m, at least 0.5m from the fence. No ornamental grasses or bamboo shall be included.

The sewer and stormwater pipes

107. The applicants claimed the roots of the respondents’ trees had persistently and severely damaged their terracotta sewer and stormwater pipes since 2010, but the applicants failed to substantiate the claim with sufficient evidence.

108. Based on his research, Mr Christiansen contended the terracotta pipes may last 120 years and junctions between the pipes would ordinarily remain intact if not for the roots of the respondents’ trees. Mr Christensen depicted a scenario whereby force exerted by roots of the respondents’ trees damaged pipe junctions and facilitated root entry but he failed to prove a causal link between the pipe damage and the respondents’ trees.

109. Conversely, the respondents claimed existing trees growing nearby and stumps from trees removed from the applicants’ yard in the past may be current or past sources of roots in the pipes. Where there is ambiguity as to the source of the roots, it is incumbent on the applicants to identify the particular tree(s) on the respondents’ property that the applicants contend are the cause of the problem. See Lewis v Tilney [2009] NSWLEC 1042 at paras [43] to [55].

110. The applicants provided reliable root identification evidence undertaken by Dr Matthew Lawrence, a renowned DNA expert. The DNA analysis determined that roots extracted from the pipes belonged to the genus Ficus i.e. they were Fig roots.

111. In their submission, the applicants attributed the roots to a Fig tree in the Austin’s front yard, but the alleged Fig tree was misidentified. No Fig species were identified by the applicants or apparent on the Austin’s land but there was a very large Hill’s weeping Fig (Ficus microcarpa var. hillii) growing in the backyard of the respondents’ rear neighbour.

112. Notwithstanding that the onus is on the applicants to identify the source of the roots damaging the pipes and prove a causal link, on the balance of probability and in the absence of other Fig trees nearby, this neighbouring Hill’s weeping Fig was the likely source of the Fig roots causing blockages in the applicants’ pipes.

113. While this required the roots of the Hill’s weeping Fig to be growing far beyond the canopy of the tree, this is a typical characteristic of this species and the Genus Ficus, generally. It is common for roots of large Fig trees to grow opportunistically where conditions are conducive and to occupy and block pipes. This scenario is reported in many precedents under the Trees Act, such as Chew v Frykberg [2025] NSWLEC 1355.

114. I was similarly satisfied that large raised roots growing across the applicant's backyard that appeared to have damaged the applicants’ garage, were Fig roots that probably belonged to the same Hill’s weeping Fig. Mr Christensen had severed and killed some of these roots.

115. Based on ‘camera vision’, the applicants claimed the points of root entry were at the pipes’ joints. This was likely to result from deterioration at joints due to age-based wear and tear, regardless of whether the pipes had incurred extraneous forces, as Mr Christensen had speculated.

116. As they age, rubber rings within the junctions of terracotta pipes progressively lose flexibility and deteriorate. Similarly, over time, mortar around junctions reduces in strength, becomes fragile and develops fissures. This is exacerbated by natural movement of the soil as a result of moisture level changes over time. Consequently, fluids seep from junctions and roots grow opportunistically towards and within these areas of increased moisture. Once fine root hairs penetrate into pipe junctions, they flourish in ideal growth conditions provided by ample moisture, oxygen, and nutrients.

117. The applicants submitted plumbing receipts, which noted multiple instances of root clearance from the pipes with water under high pressure, since 2010. The cumulative impact of such high-pressure water was also likely to have damaged pipe joints. The respondents contended the trees would have been relatively small when roots were initially detected in the applicants’ pipes in 2010.

118. Terracotta pipes 60–70 years old are rarely encountered. As a result of pipe damage and or deterioration of seals at junctions, as described above, terracotta pipes have usually been replaced with PVC pipes prior to reaching such an age, as was the case with the respondents’ pipes. PVC pipes have been commonly used for at least 40 years. Due to the superiority of the seals when PVC pipes are properly installed, tree root entry into PVC pipes is rare.

119. The applicants’ plumbing receipts repeatedly recommended replacing the terra cotta pipes with PVC but the applicants apparently disregarded this advice. The respondents reported multiple instances of sewage consequently overflowing from damaged terracotta pipes along the parties’ common front boundary.

120. The applicants’ own root identification evidence, sourced from a renowned DNA expert, confirmed that the roots sampled from the applicants’ pipes originated from a species of Fig, none of which were present on the respondents’ land. No other species of trees were identified in the DNA analysis, nor did the applicants provide evidence, beyond mere speculation, of other tree species occupying the applicants’ pipes. Therefore, on the balance of probability, the applicants failed to prove the respondents’ trees were causing blockages or damage to their terracotta pipes. Consequently, the applicants proposed order for the respondents to replace or repair the terracotta pipes is refused.

Compensation for plumbing works

121. The applicants’ DNA root analysis identified roots in the terracotta pipes as a species of Fig, yet no Fig species were identified on the respondents’ land. Therefore, the applicants failed to prove a causal link between the respondents’ trees and terracotta pipe damage. Consequently, the respondents are not liable to pay compensation to the applicants for past plumbing expenses related to such terracotta pipe damage.

Tile damage

122. I was satisfied by the applicants’ claim that the lean of the wall had resulted in about half a square metre of surface tiling adjacent to the wall being compressed and raised as secondary damage due caused by the trees. While I could not ascertain if any tiles were damaged or missing, some additional tile damage may occur during wall dismantling and replacement. Although the respondents shall pay 75% of the cost of repairs, the applicants’ proposed order for the respondents to replace the tiles, but with the tile pattern and colour to be subject to the applicants’ approval, was not viable. Such a recipe was likely to result in unnecessary and avoidable disagreement, particularly when the tiles were more than 50 years old and likely to be difficult to match. Particularly considering the relatively inconspicuous location of the tile damage, the structure of orders for tiling shall be similar to other elements of the works.

123. The applicants and respondents shall each obtain and exchange one quote from a suitably qualified tiler to re-tile the approximate half square metre area of damaged tiling plus any tiling damaged during wall dismantling and reconstruction. The quote shall itemise the cost of any replacement tiles, which shall match existing tiles as closely as practicable. The applicants shall engage and pay one of these two tilers to undertake the works. Upon completion, the respondents shall pay the applicants 75% of the cheaper quote by EFT within 7 days of receipt of a paid itemised invoice from the applicants.

Compensation for cost of protective barrier and DNA testing

124. The applicants claimed $290.99 compensation for a barrier erected to protect life and property from damage in the event of the dividing fence wall falling, and $267.00 paid for DNA root identification.

125. The respondents contended that the applicants’ protective barrier, which was apparently constructed from pine pallets, was inadequate and not fit for purpose. Additionally, the respondents contested liability for the cost of the barrier because they had not been consulted prior to the barrier’s installation.

126. Instances where applicants become aware of damage being caused to their property (or incidental to such damage) and repair or take measures with respect to such damage, without providing the tree owner opportunity to assess the damage or be consulted about the method and cost of repairs or damage response have also been considered under s 12(h). This failure to consult the respondents may be taken into account by the Court when considering whether or not to make orders relating to the damage.

127. In Osborne v Hook [2008] NSWLEC 1231; at [51], Moore SC and Thyer AC determined (in that case in response to damage to concrete) that, as a matter of discretion, because of the failure of the applicants to give the respondents adequate notice or opportunity for consultation prior to responding to the damage, “we ought not entertain any claim for damages on this occasion”. I made a similar finding in Williams v Robertson [2022] NSWLEC 1118, with respect to an absence of consultation prior to tree pruning.

128. The applicants provided no evidence of having consulted with the respondents about intending to claim compensation for the cost of the barrier or its installation. Nonetheless, the respondents had repeatedly requested the applicants install a protective barrier and the respondents’ inaction removing the trees was a major cause of the progressively increasing wall lean and damage, and thus the imperative for such a barrier.

129. Under these circumstances, I find the parties should equally share responsibility for their respective omissions. Therefore, orders shall be made for the respondents to compensate the applicants $145.50, which is 50% of the paid invoice for the barrier. Although the barrier appeared to be constructed from pine pallets, I adduced insufficient evidence to assess its fitness for purpose.

130. With respect to the applicants’ claim for compensation for the cost of root DNA testing, Commissioners do not have power to grant orders for DNA testing, expert reports, or legal fees. Claims for such costs require the lodgement of a Notice of Motion with the Court, which is heard by a registrar or a judge.

Conclusion

131. The Besser block boundary wall was built in 1969, and the respondents were initially alerted about wall damage in 2012. Although both parties largely blamed the other for preventing dispute resolution in the interim, I was satisfied that both were fairly equally responsible. Therefore, when considering relative causes of damage, I deemed the wall to be about 50 years old.

132. Consistent with the respondents’ report from a suitably qualified, experienced arborist, I found the trees were the primary cause of wall damage. The respondents’ email log showed ongoing denial or minimisation of the trees’ role in causing wall damage up to December 2022, yet I found no evidence of the respondents having clarified the trees’ impact on the wall with an expert arborist or engineer until recently. I am satisfied this omission was a ‘negligent act’ by the respondents under s 8 of the Fencing Act.

133. I am also satisfied the wall’s excessive pillar spacing and height, insufficient reinforcement, and age-based deterioration contributed to the damage.

134. Therefore, the applicants shall have first option to build a replacement wall, and the respondents shall be liable for 75% of the cheaper of the parties’ quotes for a ‘like for like’ replacement wall. While the applicants proposed the respondents pay the full cost of a new wall built to current standards, this would not be a ‘like for like’ wall. Instead, it would be a new wall of far better quality and structural condition than the existing wall. As determined in Yared; at [112], it would be unreasonable for the respondents to be liable for the full cost of a replacement wall that would almost certainly improve the value of the applicants’ property.

135. For similar reasons, the respondents’ contribution shall not include the cost of engineering drawings, DA preparation and lodgement or costs of wall reinforcement, or of foundations that exceed requirements of the respondents’ 0.6m wall because none of these costs were incurred with the original wall and the respondents’ proposed fence is a ‘sufficient fence’. It is standard procedure under the Fencing Act for a party electing to construct a fence of higher quality and cost than a ‘sufficient fence’ proposed by neighbours, to pay any extra costs. Further, such costs relate to property improvement for the applicants.

136. Consistent with the determinations in Bentley*;* at [10]-[13], depreciation of the walls’ value due to wear and tear over about 50 years, and the walls’ design and structural deficiencies, are relevant considerations in apportioning the parties’ contributions.

137. Roots extracted from the applicants’ pipes were identified by DNA testing as the genus Ficus*,* no specimens of which were present amongst the trees subject of the application, nor were any apparent on the respondents’ land. Consequently, the applicants’ proposed orders for the respondents to repair or replace the applicants’ terracotta pipes and pay compensation for past plumbing expenses are refused.

138. I am satisfied that tile damage was secondary damage caused by the trees. Therefore, the respondents shall be liable for 75% of the cheaper of the parties’ quotes for re-tiling and for replacement tiles, if required.

139. The applicants claim for compensation for the cost of root DNA testing requires lodgement of a Notice of Motion which is heard by a registrar or a judge.

140. Given that the proceedings resulted in less extensive works than envisaged in the applicants’ proposed orders, a structural engineer was not required to supervise the works or engage suitable subcontractors.

Orders

141. The Court orders that:

142. The application is approved, in part.

143. The respondents shall compensate the applicants $145.50, equivalent to 50% of the cost of safety barrier installation, by electronic fund transfer (EFT) within 7 days of the date of these orders.

144. The respondents shall engage and pay qualified licenced builders or qualified licenced landscape gardeners, with all appropriate insurances (the contractors), to dismantle the Besser block common boundary wall (the wall), block by block, down to the approximate level of the respondents’ poolside garden bed (the garden) and remove debris, within 30 days of the date of these orders. Mattresses or similar padding shall be used to protect the applicants’ property during wall dismantling, and the works shall include removal of the blocks or stacking for re-use, subject to the blocks’ condition and the parties’ preferences.

145. Within 30 days of the date of these orders, each party shall obtain and exchange one itemised quote from a qualified structural engineer to inspect the existing foundation (once it is exposed per Order (6)) and report on, (i) whether the existing foundation is sufficient for each party’s proposed wall, or, if not, (ii) supplementary works required to make the existing foundation sufficient for each party’s proposed wall, or, (iii) whether the existing foundation needs replacement for one or both proposed walls, and, (iv) to provide drawings and specifications for a foundation suitable to support the respondents’ 0.6m retaining wall, based on the outcome of (ii) and (iii). Within 35 days of the date of these orders, the parties shall select a structural engineer. If the parties cannot agree on the engineer, the engineer with the cheapest quote shall be selected. The respondents shall engage the selected engineer to inspect the foundation and report to both parties by email within 75 days of the date of these orders and shall pay the engineer within 7 days of their itemised invoice. The applicants shall pay the respondents 25% of the cheaper quote by EFT within 7 days of receipt of the itemised paid invoice.

146. The respondents shall engage and pay suitably qualified AQF Level 3 arborists, with all appropriate insurances, to remove all 9 trees from the garden to near garden ground level and remove debris, within 40 days of the date of these orders. The palms shall be dismantled and lowered or dropped in small sections onto mattresses or nests of foliage. The works shall comply with the Safe Work Australia, Guide to managing the risks of tree trimming and removal work, 2016.

147. The respondents shall engage and pay the contractors to dismantle and remove or stack the remainder of the wall, expose the wall’s foundations and remove sufficient soil and roots from the garden to provide safe, clear access for subsequent wall construction, within 50 days of the date of these orders. These works shall include removal of all debris including all blocks that are surplus to either party’s requirements.

148. Within 80 days of the date of these orders, the applicants shall advise the respondents by email whether they are opting to install their proposed replacement Besser block wall. If so, within 120 days of the date of these orders, each party shall obtain and exchange one quote from the contractors (who satisfy the requirements in Order (3)) for; (i) foundations required for a 0.6m tall Besser block wall retaining the respondents’ garden, based on the engineer’s report, and, (ii) construction of a wall in the current location, comprising up to five courses of recycled Besser blocks topped with four courses of recycled Besser majestic screen blocks (to be clarified by the applicants) with pillars reinforced with concrete, at 3m spacing, including a functional replacement outdoor double power point.

149. The applicants shall lodge their DA as soon as practicable and commence wall construction as soon as practicable. Upon respective completion of the foundations and the wall, the applicants shall pay the contractors within 7 days, and the respondents shall pay the applicants 75% of each respective cheaper quote from order (7) by electronic fund transfer (EFT) within 7 days of receipt of paid itemised invoices.

150. If the applicants fail to complete wall construction within 12 months of the date of the orders, the option to construct the wall shall transfer to the respondents and the respondents’ liability to make further payments to the applicants shall lapse.

151. If, within 80 days of the date of these orders, the applicants advise the respondents by email that the respondents may proceed with their preferred fence, or the applicants fail to advise the respondents by email within 80 days of the date of these orders that the applicants opt to install their proposed block wall, or the applicants fail to complete wall construction within 12 months of the date of the orders, within 40 days of the date of one of these three triggers, each party shall obtain and exchange one quote from the contractors (who satisfy the requirements in Order (3)) for a ‘sufficient’ 1.8m high timber lap and cap paling fence with timber rails on the respondents’ side and with steel posts concreted into a 0.6m high recycled Besser block retaining wall with sufficient foundations to retain the respondents’ garden, based on drawings and advice in the engineer’s report.

152. The respondents shall commence fence construction as soon as practicable. Upon completion of the foundations and the wall, the respondents shall pay the contractors within 7 days, and the applicants shall pay the respondents 25% of the cheaper quote from order (10) by electronic fund transfer (EFT) within 7 days of receipt of a paid itemised invoice.

153. Prior to re-establishing the garden, the respondents shall engage and pay the contractors to install appropriate drainage behind the wall. Species planted in the garden shall be restricted to annual flowers and herbs or soft wooded perennials, with a maximum height of 1.5m, planted at least 0.5m from the fence. No ornamental grasses or bamboo shall be planted.

154. Upon at least 72 hours’ notice by email, each party shall allow all access required for the procurement of quotes, for the various works, and for efficient debris removal via their property during reasonable day time work hours. Each party shall email insurance certificates of currency and relevant licence details of engaged contractors to the other party, at least 72 hours before commencement of respective works.

……………………..

J Douglas

Acting Commissioner of the Court

**********

Amendments

14 October 2025

Pursuant to r 36.17 of the Uniform Civil Procedure Rules 2005 (the “slip” rule), the applicant has requested that the Orders be amended according to the following:

1. At Order 7, change line 5 from Order (2)) to Order (3)).
2. At Order 7, move (to be clarified by the applicants) from line 9 after “recycled Besser blocks” to line 10 after … “topped with four courses of recycled Besser majestic screen blocks”
3. Therefore, Order 7, line 10 should read, “recycled Besser blocks topped with four courses of recycled Besser majestic screen blocks (to be clarified by the applicants)…”
4. At Order 10, line 4, remove the comma between (the words) orders that…
5. At Order 10, change line 9 from Order (2)) to Order (3)).