Body Corporate and Community Management (Standard Module) Regulation 2020 (Standard Module)

IMPROVEMENTS TO LOT - where scheme by-laws required consent for works altering the external appearance of the building, structural alterations, and proper use of drains - whether respondent has complied with conditions of approval.

UTILITY INFRASTRUCTURE - whether respondent has made alterations to rainwater drainage on the roof-top area

EQUITY - equitable estoppel - estoppel by acquiescence- where no objection raised by body corporate during works or for 30 years after works completed.

Birstar v Ocean Breeze [1996] QCA 110

Kramer v Stone [2024] HCA 48

Act, ss 20, 167, 184, 276

• [1] This is an adjudication application by the Body Corporate for Syrenuse CTS 10792 against Luciano and Laura Sandrin, owners of Lot 23, (the respondents) in a long-running dispute regarding unapproved alterations to a rooftop area. The body corporate committee passed a Flying Minute Resolution on February 6, 2025, authorizing the adjudication application.

• [2] The applicant body corporate seeks the following outcomes;
  1. An Order that the respondent modify their lot within 3 months to drain water to the existing central drainage system or an approved alternative.
  2. If the respondent fails, the applicant seeks authorization to enter the lot, carry out the necessary work, and recover the costs as a debt.
  3. Orders for the respondent to either obtain consent for or remove the unauthorized enclosure of the pergola on the roof garden within 3 months.
  4. If the respondent fails, the applicant seeks authorization to enter the lot, remove the enclosure, and recover the costs as a debt.
  5. Reimbursement of the conciliation application fee ($220.60).

• [3] Syrenuse community title scheme consists of 26 lots and common property, established on 21 September 1981. It is regulated by the Standard regulation module.
• [4] The application seeks orders related to works undertaken some 30 years ago, on the rooftop area of Lot 23. More specifically, the applicant says the enclosure of a rooftop pergola, and alterations to the drainage system has resulted in nuisance and damage to common property.
• [5] The Body Corporate alleges that the respondents have failed to obtain/ provide required approvals and have caused ongoing issues with water drainage and building staining. The application also seeks reimbursement for conciliation and adjudication fees, citing the respondent's failure to participate in conciliation.
• [6] The respondent's lot is located on the top levels of the building and originally had an open pergola and family room, with a central drainage system. In 1993 conditional approval was given for a roof on the pergola, but the applicant says the attached conditions, including requirements for an engineering certificate and indemnity, were never met.
• [7] The applicant refers to "unapproved works," including the enclosure of the pergola (which is now a habitable area) and covering the Central Drainage System. The applicant says that blocking the central drainage has caused water to pool and stagnate. The stagnant water discharges slowly through spitters, staining the building and creating a nuisance.

• [8] The original design included an open pergola and family room on level K. Conditional approval was given in 1993 to construct a roof on the pergola and partially enclosure the pergola with windows. However they say the respondent later completely enclosed the pergola without approval and is now a habitable area".[1]

• [9] The applicant says that water now "pools on the narrow strip of common property between the enclosed habitable area and the external walls of the rooftop before reaching a sufficiently high level to discharge through the spitters".
• [10] After rain, the pooling water "stagnates and continues to trickle through the spitters for long periods, which the applicant says is causing damage to the rooftop as well as staining the exterior of the building as water slowly discharging from the spitters down the side of the building for days afterwards. [2]

• [11] The applicant says the unapproved works are "causing a nuisance and a hazard to the occupiers of lots beneath the respondent's lot",[3] with rainwater cascading and dripping onto balconies.[4] This is alleged to contravene section 167 of the Act which prohibits using a lot in a way that "causes a nuisance or hazard" or "interferes unreasonably with the use or enjoyment of another lot."
• [12] The applicant relies on the respondent's failure to comply with 1993 approval conditions and statutory requirements concerning common property (the Central Drainage System is considered common property) and nuisance provisions of the Act.
• [13] The Body Corporate asserts the Unapproved Works required approval under both past and current by-laws, and that the respondent has failed to meet statutory requirements.

• [14] The scheme by-laws which applied prior to July 1997, required consent for works altering the external appearance of the building,[5] structural alterations[6], and proper use of waste pipes/drains.[7]
• [15] The current by-laws, applicable from July 1997, require consent for works which involve damage to common property[8] and altering the external appearance.[9] The applicant states, "Irrespective of when the Unapproved Works were completed by the respondent, they required the applicant's approval".[10]

Failure to Comply with 1993 Approval Conditions:

• [16] Conditional approval for the pergola roof in 1993 required an "engineering certificate" and a "certificate of indemnity," which "are yet to be met".[11]

Interference with Common Property (Central Drainage System)

• [17] The Central Drainage System is argued to be "common property" under "Section 20(b) of the Act" as it "extends through multiple lots and common property and supplies utility services... to all lots in the scheme".[12] The decommissioning of this system is considered an improvement to common property requiring consent, which was not obtained.[13]

Building Units and Group Titles Act 1980

• [18] Section 51(a)(ii) of BUGTA (applicable until July 1997) prohibited interfering with drainage through pipes.
• [19] The application also addresses a potential defence of estoppel by acquiescence, arguing against it by stating there was no inducement and the respondent undertook works without required approvals.
• [20] The application is accompanied by a conciliation certificate and various attachments supporting the body corporate's claims. A conciliation application was made in October 2024, but the respondent did not attend, and the conciliator determined they did not make a reasonable attempt to participate. The applicant seeks reimbursement of the conciliation application fee.

• [21] Pursuant to section 243 of the Act, the respondent and all lot owners were invited to make submissions regarding the application.
• [22] The owner of lot 16 says there is an almost constant water discharge from the rooftop. This constant dripping is particularly noticeable on their rear balcony, staining the tiles. Continued dripping onto one of their air conditioning systems has caused it to rust excessively compared to the other air conditioning unit which shows almost no rust or damage.
• [23] It was only when Body Corporate committee members inspected the roof top apartment that the source of this "drip" became apparent. The lack of a central drain outlet results in water stagnating and discharging from the roof spitters long after any rainfall.
• [24] They believe the owners of lot 23 blocked off the rooftop drainage system so that all drainage is directed through the spitters. The spitters were not designed as a primary source of water discharge.
• [25] Another submission was received from Mr Ray Giarola who is the owner of lot 19 and also a committee member. Mr Giarola is also a qualified Architect and has spent a considerable amount of time examining the original architectural plans, the 1993 plans detailing the lot 23 works and other records of the body corporate.[14]
• [26] He says that Lot 23 was given permission to undertake certain works in 1993 but believes that at the same time they undertook work that was not approved, including complete enclosure of the outdoor garden area and blocking the central Rain Water Outlet (RWO ) to which all rainwater fell.
• [27] He believes there was originally a central RWO in the roof garden area, being the designated point where rainwater collected from the roof discharged into the stormwater system. He also says that the rooftop was built so that the floor falls away from the parapet and now it cannot drain away. As rainwater cannot drain through the RWO, it ponds on the perimeter sunhood area and when it reaches a certain level, discharges through the spitters. When the water sits for a period of time, black mould grows and is eventually discharged through the spitters down the walls to the units below.
• [28] On 26 March 2025, Mr Giarola wrote to Stewart Magill, a Building Certifier, attaching copies of various documents including original plans and documentation relating to subsequent improvements. He asked the following questions:

Q1. Can stormwater from the roof be discharged through the spitters?

Q2. Can the perimeter area between the building & the upturned parapet be determined as a sunhood & if so, can this area be re graded so that stormwater is discharged through the spitters?

• [29] In a reply dated 10 April 2025, the Building Certifier stated that in his opinion:

1. Stormwater drainage must comply with AS/NZS 3500.3. The roof must be connected to a Rain Water Outlet, so it cannot be discharged through the spitters, &

2. The concrete sunhoods can be discharged through the spitters.[15]

• [30] On 11 April 2025, the committee received a report from Dr. Noel Robinson the original architect of the building, stating:[16]
  1. The open to the sky roof gardens were intended to be drained to a rain water outlet (RWO) positioned in the middle of each roof garden.
     1. The drainage of the sunhoods relied primarily on the perimeter spitters.
• [31] Also on 11 April 2025, a flying minute was sent to BC members to approve Covey Hydraulic Engineers complete a roof drainage plan for a fee of $5,500 - $6,500. I believe they considered a proposal to installation new RWO's on the rooftop area with a stormwater pipe running from the underside of the upper floor slab to the internal stormwater system.[17]
• [32] In conclusion, he believes the committee has provided enough evidence, including independent reports to direct Unit 23 to:

1. Obtain Building & body corporate approvals for enclosure of the pergola.

2. Obtain Building & body corporate approvals for installation of a stormwater solution as outlined by Covey.

• [33] The Respondent says the dispute revolves around alleged breaches of by-laws by the specifically concerning unapproved works to a roof garden, enclosure of a "pergola," and alterations to stormwater drainage.
• [34] The Respondent initially raises a jurisdictional argument, asserting that the Applicant failed to issue a valid contravention notice alleging a breach of by-laws as required by the BCCM Act, thereby rendering the application invalid.
• [35] The Respondent also contests the factual basis of the Applicant's claims regarding unauthorized modifications to drainage and enclosures, and argues that much of the work was either original to the building or previously approved, or that the issues stem from the Applicant's poor record-keeping and common property maintenance.
• [36] Finally, the Respondent argues that the principle of estoppel by acquiescence is applicable due to the nearly 30-year delay in raising these concerns, and seeks dismissal of the application with costs, characterizing it as frivolous and vexatious.

• [37] The Respondent's primary argument is a Jurisdictional Issue. They contend that the Adjudicator lacks jurisdiction to hear the dispute because the Applicant failed to issue a valid contravention notice as required by Section 184(2) of the BCCM Act. The Respondent argues that the purported contravention notice dated January 19, 2024, was invalid as it lacked sufficient details to identify the contravention. The Applicant was repeatedly notified of this jurisdictional issue but proceeded with the application without rectifying it. The Respondent asserts that compliance with Section 184 is a mandatory precondition.

Substantive Dispute Regarding Works and Drainage:

• [38] Approved Works: The Respondent maintains that the enclosure of the rooftop garden area with glazed windows and sliding doors was approved by the Applicant at an EGM on March 26, 1993. The Respondent highlights that the Applicant's records are incomplete and do not contain the plans minuted as approved, making it difficult for the Applicant to establish non-compliance.
• [39] Spitters and Drainage: The Respondent states that "spitters" (water discharge pipes) were part of the original construction of the building and not installed by the Respondent.
• [40] The Respondent also states that the roof garden was constructed at a higher level than the surrounding common property sunhoods, making it impossible for water to flow from the common property onto the lot's internal drainage system. The Respondent asserts that this information was provided to the Applicant prior to the application.
• [41] Storm Shutters: The Respondent admits that storm shutters were installed without the Applicant's approval but is willing to seek retrospective approval.
• [42] Utility Infrastructure: The Respondent challenges the Applicant's characterization of the rainwater outlet as common property, arguing that it collects stormwater solely from the lot and is within the lot boundaries, aligning with the definition of utility infrastructure not considered common property under Section 20(1) of the BCCM Act.
• [43] Nuisance: The Respondent denies that their works caused any nuisance, attributing any issues like stagnant water to faulty waterproof membranes on common property, which is the Applicant's responsibility. They also state that the "spitters" are an "ordinary and accustomed use" and part of the building's design for disposal of rainwater from the sunhoods.
• [44] Onus of Proof and Evidence: The Respondent emphasizes that the Applicant bears the onus of proving a breach of by-laws and that the Applicant's reliance on outdated plans and incomplete records is problematic. Expert opinions from the original architect, Mr. Noel Robinson, support the Respondent's claims regarding the original design and drainage.
• [45] Estoppel by Acquiescence: The Respondent submits that the Applicant's nearly 30-year delay in raising concerns about the works, despite knowing they were conducted, and approvals were required, should bar the application through estoppel by acquiescence.
• [46] Application for Costs: The Respondent says the Applicant has changed the relief sought from the conciliation application to this application. This application seeks orders for the Respondent to reimburse the conciliation application fee, conduct modifications to lot drainage, and either obtain consent for or remove an unauthorized enclosure of the pergola on the roof garden. If the Respondent fails to comply, the Applicant seeks authorization to enter the lot, carry out the work, and recover costs.
• [47] Therefore, in summary the Respondent says:
  • the Applicant is claiming that nuisance was caused by unapproved works, specifically regarding water runoff from building spitters in the sunroof area, even though the spitters are part of the original building design
  • the Applicant has failed to provide sufficient evidence to demonstrate a nuisance, such as "before and after" modelling or proof of altered water flow.
  • any issue with stagnant water in the sunroof area (which is common property) stems from common property infrastructure for which the Applicant is responsible.
  • the Applicant's significant delay in bringing the application should bar the claim, citing the principle of estoppel by acquiescence due to the Applicant's long-standing knowledge of the works without objection and their alleged failure to maintain proper records.
• [48] The Respondent says the application should be dismissed with costs because it seeks inappropriate relief, relies on inconsistent and incomplete material, and is vexatious and misconceived.

• [49] The construction of Syrenuse was completed in 1981. This application relates to works undertaken on the rooftop area of Lot 23 in 1993, some 30 years ago. The applicant Body Corporate alleges that the respondent failed to obtain/ provide required approvals for certain works which have allegedly caused ongoing issues with rainwater drainage. The applicant says that in the course of undertaking these works, alterations were made to the drainage of stormwater from one or more rain water outlets (RWO's) in the rooftop area, resulting in ponding of rainwater and discharge of rainwater through spitters located in the rooftop parapets.
• [50] The body corporate says the building drainage system was designed so that water run-off from the roof top area would go to a central roof drain. It says the respondent enclosed the rooftop garden without proper approval and blocked central rainwater drains. Further, they say this has led to rainwater ponding, stagnating and causing damage to the rooftop waterproofing membrane. Accumulated rainwater discharges through secondary "spitters," around the perimeter of the rooftop and runs down the exterior of the building onto balconies and common property below.
• [51] Not surprisingly, the effluxion of time presents a number of problems in the resolution of this dispute. The Respondent argues that the Applicant's case relies on incomplete body corporate records, incomplete data and an erroneous understanding of the building's design. They also argue that the principle of estoppel by acquiescence is applicable due to the Applicant's long-standing knowledge of the works without objection, and their alleged failure to maintain proper records.

• [52] The Respondent initially raises a jurisdictional argument, asserting that the Applicant failed to issue a valid contravention notice alleging a breach of by-laws as required by the BCCM Act, thereby rendering the application invalid. I am in agreement that having no knowledge of when the unapproved works were completed, it would be unreasonable for the applicant to now issue the respondent with a notice of a continuing breach of a (current) body corporate by-law and it would be impossible for the applicant to now issue the respondent with a notice of a continuing breach of a (previous) body corporate by-law.
• [53] However, I also note that while the applicant refers to by-law contraventions, the application does not explicitly seek remedies regarding their alleged non-compliance. The applicant relies on the failure of the respondent to comply with the conditions imposed on the approval granted at the 1993 EGM, and the statutory requirements for body corporate consent for improvements to common property, as the basis of the dispute.
• [54] In particular, the applicant says that when the respondent enclosed the rooftop pergola and converted it into a habitable room, they decommissioned the Central Drainage System. The applicant further states that decommissioning of common property is, for the purposes of the Standard Module, an improvement to the common property requiring the applicant's consent, and the applicant has not approved the decommissioning of the Central Drainage System.
• [55] As mentioned, certain works were undertaken by the respondent in 1993. While permission was given for roofing and partial enclosure of a pergola, it is alleged that the respondent failed to comply with conditions of approval. It is also claimed that they contravened of plumbing and drainage regulations.[18] The applicant's approval of the 1993 renovations was conditional on the respondent complying with all building requirements of the Maroochy Shire Council and other authorities, and supplying an Engineering Certificate and Certificate of Indemnity upon completion.
• [56] The minutes of the Extraordinary General Meeting held on 26th March 1993 record that the following motions was carried :

2. That the proprietors of Lot 23 be authorised to effect improvements to the lot by installing a flat roof over the existing pergola within the lot as show on the plan annexed hereto and marked with the letter "B" subject to the following conditions:

1. The proprietor complies with all building requirements of the Maroochy Shire Council and an other authority having jurisdiction for the construction and installation of such improvements; and
2. Such improvements be constructed with new and good materials in a workmanlike manner; and
3. Such improvements be constructed at the proprietor's expense; and
4. The proprietor shall be responsible for the performance of the duty of the Body Corporate under Section 37(1)(c) of the Act in respect of the improvements; and
5. The proprietor be responsible for the rectification of any damage (if any) occasioned to any other lot in the building or to the common property as a result either directly or indirectly of the construction of the improvements.

Mr Knezic of Lot 24 agrees, on behalf of proprietors of Lots 23 and 24 to supply the body Corporate with an Engineering Certificate completion of the improvements which would include a Certificate of Indemnity regarding improvements.

• [57] It is evident that on 14 September 1993, the respondent was issued with Building Permit 931241 by the Maroochy Shire Council for work to be undertaken on the lot 23 roof terrace, level K, in accordance with the approved plans.
• [58] Attached to the permit were the plans (3 pages of drawings) prepared by the respondent's architect, and bearing the Council approval stamp dated 14 September 1993.[19] it is evident that the roof terrace originally included an open pergola and family room. The approved alterations to the open pergola were as follows:
  • Installation of 3 additional 250 x 50 F17 timber pergola beams (rafters)
  • Fixing new 75 x 38 roof battens to the rafters
  • Installation of new Spandek colorbond metal roof sheeting over the battens
  • Installation of new 6mm fibre cement sheeting as ceiling, attached to the underside of the rafters
  • Installation of new aluminum framed glazed sliding windows to the Northern & Southern sides of the external area, with the seaside facing side of the pergola remaining open.
• [59] I also note that by letter dated 19 May 1993, Cardno & Davies, Consulting engineers advised the Maroochy Shire Council they had examined the architectural drawings of Noel Robinson "that detail enclosure of the roof garden area" and were able to confirm that the design wind loading was 53 m/ sec. and that the framework would provide adequate resistance to increased lateral wind loading.
• [60] The applicant argues that while conditional approval was given to construct a roof on the pergola and partial enclosure with windows, the respondent later "completely enclosed the pergola so that it is now a habitable area.[20] The applicant body corporate says these works also involved unapproved alterations to the drainage of stormwater from one or more rain water outlets.
• [61] I understand that close to 30 years elapsed before the body corporate investigated the source of water dripping from the rooftop spitters. When Body Corporate committee members inspected the roof top area in around 2022, the source of this "drip" became apparent. Rainwater was accumulating on the "Sunhoods". They believe that previously rainwater on the sunhoods ran to central drain outlets,[21] resulting in water stagnating and slowly discharging from the roof spitters after any rainfall.
• [62] On 4 August 2022, the body corporate manager wrote to the respondents noting that in around 1993 certain approved works had been undertaken to the lot 23 pergola area. They also noted that it appeared that the following non-approved/additional work had also been completed:
  • Installation of Storm Shutters to the existing glazed panels
  • Full glazing enclosure along the seaside wall
  • Capping off the RWO (rainwater outlets) & downpipes and in lieu, use of spitters as the primary source of stormwater discharge, which is not their original intention, and is causing nuisance to the units below.
• [63] The applicant says the respondent did not obtain the necessary approvals for these additional works and Council records show no such approvals (other than an approval of unenclosed renovations to the rooftop area), and the required certificates were not provided. The conditional approval for the pergola roof in 1993 required an engineering certificate. While the applicant says that this condition was not met [22] it is evident that by letter dated 19 May 1993, Cardno & Davies, Consulting engineers advised the Maroochy Shire Council they had examined the architectural drawings and were able to confirm that design wind loading was 53 m/ sec. and that the framework would provide adequate resistance to increased lateral wind loading.
• [64] I note that Mr Giarola, who is a committee member and also a qualified Architect, has recently studied the design plans, the 1993 plans detailing the lot 23 works, and other records of the body corporate. He says that Lot 23 was given permission to undertake certain works in 1993 but the respondent also undertook work that was not approved, including complete enclosure of the outdoor garden area and blocking the central Rain Water Outlet (RWO) to which all rainwater fell, causing all stormwater to discharge through the secondary spitters.
• [65] He says design plans show primary stormwater discharge via sumps and downpipes, with spitters as a secondary, overflow mechanism, approximately 50mm above the concrete roof level.[23] He believes the respondent blocked off these primary rainwater outlets and altered the rooftop's fall by packing concrete between the tiled pergola area and the common property "Sunhoods" surrounding the lot. He also says it is evident from design plans[24] that on other levels, such as level 11, the concrete roofs fall to the RWO's as the primary means of stormwater discharge.
• [66] In addition to this, an extract from Noel Robinson's Drawing 'DETAILS' 1302.50.C affixed to the bottom of the drawing shows a downpipe & sump detail on this same concrete roof as above, outside of the roof garden. If all water was going to discharge over the parapet edge as a primary source, a sump would not have been required. The applicant says the spitters are 50mm above the level of the sunhoods. The "for construction" concrete roof slab levels are shown falling away from the spitters to the rain water outlets.

• [67] The respondent says the original construction of the Lot included a roof-garden and pergola area that was paved and the paved area was 150 mm higher than the common property surrounding the lot. Therefore, they argue the allegation that water falling on the common property was intended to be conveyed across the lot cannot be true.[25] Accordingly, it is argued that the renovation work did not affect the spitters or drainage.
• [68] The spitters were part of the original construction. The respondent says that the All water falling onto the common property 'sunhood' was intended to be directed to the spitters. In terms of the allegation that rainwater was collected internally, this was only true of rainwater falling onto that part of the lot referred to as the roof garden area. That water either fell on an existing roof, and was conducted away by pipework, or fell on the rooftop garden, and was discharged through the rainwater outlets located on that area.
• [69] The respondent says rainwater outlets were located wholly within the boundaries of the lot and only allowed the collection of water falling on the area of the lot (the roof garden). The surface area of the roof garden was approximately 150 mm above the height of the common property sunhoods. The common property sunhoods are surrounded by a parapet with the spitter pipes. The spitter pipes were part of the original design of the building as the primary discharge for water falling on the common property sunhoods as it was impossible for the rainwater falling on the common property sunhood to discharge through the original roof garden area due to the differences in height in those surfaces.
• [70] I note the applicant's claim that paving in the lot 23 roof garden comprised ungrouted brick pavers on a sand base sitting on the concrete slab which falls to the central rain water outlets. However I do not believe there is evidence to support the claim that the flooring system was designed to allow rain water to pass through the gaps between the brick pavers and drain through the bedding sand into the central rain water outlets.
• [71] The respondent says that in order to prevent the continual water leaks and damage to lots 23 and 24, the original architect for the building, Mr Noel Robinson of Noel Robinson Architects, was engaged in or around early 1993 to prepare plans to enclose the rooftop garden areas with glazed windows and sliding doors. The engineering advice that they received at the time was that a failure to fully enclose fully the pergola area, would result in the loss of the roof due to wind pressures.
• [72] By resolution on motion 2 at the AGM on 26 March 1993, the applicant approved the proposed installation of the roof and enclosure of the roof garden area.[26] However, the Applicant's records do not include the plans minuted as "approved".
• [73] The difficulty with comparing the "Plan" relied upon by Mr Giarola is that it is not the final construction plan, and may not reflect the scheme as constructed. The plan relied upon is Drawing 26 "Issue D" but Mr Robinson has advised the respondent that that "Issue F" was produced 6 months later[27] and therefore issue D should not be relied upon.
• [74] Further, I note that at item 3.4, "Conclusion" on page 4 of Mr Giarola's Report, he states that "We are unsure what was being discussed at the Body Corporate meetings in October 1992 (11 months prior) & March 1993 (4 months prior), as no annexures were attached." This indicates that the Applicant does not have material to establish that the Respondent did not have approval, and the Applicant cannot establish that the works were not authorised.
• [75] In any event, the Respondent has sought advice from Mr Noel Robinson, the original architect for the Scheme, who was also engaged in 1993 to prepare the plans and obtain the council approval to the alterations the subject of the Applicant's allegations. In his correspondence dated 11 April 2025[28] Mr Robinson states, inter alia :

With regards to the original building design I find evidence to suggest that:

• the open to sky roof gardens were intended to be drained to a rain water outlet (RWO) positioned in the middle of each roof garden.
• The drainage of the sunhoods relied primarily on the perimeter spitters.
• The roof gardens had a paved floor finish that was built up on bedding on top of the concrete roof slab.
• A vertical change in level existed at the interface of the roof garden and the surrounding common property sunhoods - the roof garden being higher than the sunhoods due to the thickness of the paving and bedding and a possible step in the concrete slab.
• The paving on the roof garden was intended to fall to a central rain water outlet - which provided the primary means of drainage to the roof garden.
• It should be noted that Drawing 26 Issue D (referred to by the body corporate as evidence that the roof garden rain water outlets were a primary point of discharge for the roof) is dated May 1980 which is 6 months earlier than drawing 51 Issue F and shows significant inconsistencies with the latter drawing. This suggests that drawing 26 Issue D is outdated and should not be relied upon.
• It is likely that in May 1980 it had not yet been proposed that there be any occupation or habitable rooms on level 11. The equally spaced setout of rain water outlets and slab ridgelines on drawing 26 Issue D and drawing 27 Issue A, appear to be the drainage strategy for an 'open to sky' roofscape. I suspect that by December 1980, during the construction drawing (working drawing) stage a redesign of the level 11 had occurred, and habitable family rooms and roof gardens were now proposed.
• Due to the perimeter of the roof garden being higher than the sunhoods, the primary means of draining the sunhoods did not involve the roof garden rain water outlets but relied upon another strategy. Most logically, based upon the as-built evidence, the drainage occurred via the perimeter spitters.

• [76] This is consistent with photographs provided by the respondent. Figure 3 on page 11 of the respondent's submissions shows the unenclosed area with brick tiles/ pavers at visibly higher level than the common property outside the fence.
• [77] In addition, the photographs in Attachment 5 to the respondents submission, show the roof garden/ pergola area before it was enclosed. These photographs show the brick tiles/ pavers at a higher level than the sunhoods. In photographs on pages 64, 66 and 67 (scans 4, 6, 7) there appears to be a chrome rain water outlet grate which is flush with the uppermost surface of the brick tiles/ pavers.
• [78] I also note that in Attachment A9 to application, the third aerial photograph of the upper level of lot 23 shows the colorbond roof sheeting over the pergola battens. The roof is pitched, and it appears that guttering is fixed along the lower edge of the roof to collect rainwater which is directed to a downpipe. There is an external drainpipe which appears to run from the downpipe along the base of the wall. The photograph does not show the final destination of this pipe, but the applicant does not claim that it discharges through the spitters and I believe it is probable that it is connected to the central rainwater drainage System.
• [79] This would be consistent with the respondent's statement that rainwater falling on the lot is conveyed into the stormwater system through other means and the alleged "primary central outlet" has had no function for rainwater for thirty years.
• [80] I am of the view that the drainage of the sunhoods relied primarily on the perimeter spitters, as verified by the original architect. In this regard I also note that on 10 April 2025, the Building Certifier, Mr Magill, stated that in his opinion the concrete sunhoods can be discharged through the spitters.[29]
• [81] In any event , even if I were to find that the applicant's claims were proven, I believe that the circumstances of the case gave rise to an equitable estoppel by acquiescence. That is a type of equitable estoppel that arises where one person, with full knowledge of their rights, remains passive or silent while another person acts to their detriment in the mistaken belief that they are entitled to do so.
• [82] In the decision of Birstar v The Proprietors "Ocean Breeze" Building Units Plan No 4745 [1996] QCA 110 Macrossan CJ considered certain High Court authorities on equitable estoppel.[30] Having regard to Birstar and the recent decision of the High Court in Kramer v Stone [2024] HCA 48 (December 2024) especially paragraphs [53] to [58], one may extract the following propositions regarding the equitable principle of estoppel by acquiescence:

(a) To grant estoppel there must exist some encouragement of the assumption on which the party acting relies and this encouragement must be apparent to the party inducing the assumption. Encouragement of the assumption may be the result of silence but in that case it must be in circumstances in which the party providing the encouragement should have spoken

(b) The party making the reliance must "suffer detriment" as a result of the assumption

(c) It must in the circumstances be unconscionable to allow the representing party to depart from the assumption conveyed by it, and

(d) The relief which will be granted will be determined by the requirement of equity as it operates in the particular situation.

(a) The Respondent says they had good reason to believe that the works were authorised;

(c) The Applicant knew the works were being conducted and that approvals were required

(d) The Applicant refrained from asserting their legal rights for thirty years. According to the application, the applicant did not inspect the final works in the period between 1993 and 2022, and did not inspect the rooftop common property, utility infrastructure or waterproofing membrane during this period.

• [84] For the above reasons the application is dismissed.
• [85] Finally, the respondent seeks costs from the applicant. The Act provides that an adjudicator may dismiss an application if it appears to the adjudicator that the application is frivolous, vexatious, misconceived or without substance.[31] Where an application is dismissed on this basis, the adjudicator can order costs against the applicant up to $2,000.[32] I do not believe the applicant has made out their case do not consider that it is frivolous, vexatious, misconceived or without substance. Given these circumstances, I have not awarded costs against the applicant on this occasion.

[11] Application para 24; Giarola Report, 3.2.B Q23.12

[14] This has been done in a voluntary capacity as a member of the committee

[15] See pp 2 & 3 of Mr Giarola's submission

[18] AS3500 applied to plumbing and drainage work in 1993, as it does today under the NCC, which came into effect in 2004.

[19] Drawings 1, 2 & 3 attached to document IDR 2.

[21] Also referred to as rainwater outlets or RWO's

[22] Application para 24; Giarola Report, 3.2.B Q23.12

[23] Giarola Report see Attachments A8 & A9 to application

[25] See Attachment 13 to Respondent's submission. Also see Figure 3, below

[27] Attachment14 to Respondent's submissions

[29] See pp 2 & 3 of Mr Giarola's submission

[30] Waltons Stores (Interstate) Limited v Maher (1998) 164 CLR 387 and

Commonwealth of Australia v Verewayen (1990) 170 CLR 394.