VICTORIAN CIVIL AND ADMINISTRATIVE TRIBUNAL
civil DIVISION
CIVIL CLAIMS LIST		VCAT REFERENCE NO. C6258/2020 & C3924/2021
CATCHWORDS	
Contract to supply and install underground rainwater tank – heavy rain event resulted in floatation of the tank within the ground – whether the supplier specified a satisfactory anti-buoyancy mechanism for the tank – whether supplier effectively communicated the specifications to the customer – whether customer complied with its contractual obligations to maintain the integrity of the excavation site and exclude water ingress – whether tank fit for purpose – whether the supplier provided its installation services with due care and skill – sections 55 and 60 of the Australian Consumer Law – whether supplier entitled to claim quantum meruit for the rectification and second instalment of the tank – whether supplier entitled to interest as damages.	

APPLICANT 
(in proceeding C6258/2020)	Invisible Structures Pty Ltd ACN: 065 196 401	
RESPONDENT
(in proceeding C6258/2020)	Dansan Nominees Pty Ltd ACN: 134 800 883 t/as Hyflow Plumbing	
WHERE HELD	Melbourne	
BEFORE	Member D. Buljan 	
HEARING TYPE	Hearing	
DATE OF HEARING	29 July 2021	
DATE OF ORDER	8 September 2021	
DATE OF REASONS	8 September 2021	
CITATION	Invisible Structures Pty Ltd v Dansan Nominees Pty Ltd (Civil Claims) [2021] VCAT 1034	
Order

In proceeding C6258/2020: 
1. 	The Tribunal orders that Dansan Nominees Pty Ltd ACN: 134 800 883 t/as Hyflow Plumbing must pay Invisible Structures Pty Ltd ACN: 065 196 401 the sum of $42,744.30 plus statutory interest of $3,535.02. 
2. 	Having regard to section 115B of the Act and being satisfied that Invisible Structures Pty Ltd ACN: 065 196 401 has substantially succeeded in its claim, I am satisfied that Dansan Nominees Pty Ltd ACN: 134 800 883 t/as Hyflow Plumbing should reimburse Invisible Structures Pty Ltd ACN: 065 196 401 the application fee of $696.10 it paid in respect of its claim.
In proceeding C3924/2021: 

1. 		The proceeding is dismissed. 

D. Buljan
Member 
APPEARANCES:		
For Applicant	Mr J. Droomer 	
For Respondents	Mr D. Hoare 	

Reasons
INTRODUCTION 
1	Proceedings C6258/2020 and C3924/2021 are a claim and counterclaim arising from the supply and installation of a 60 kilolitre Rainstore3 underground rainwater detention tank (‘the tank/product’) during the commercial construction of an aged care facility at 14 Elizabeth Street Glen Iris (‘the Basscare project/the project’). 
2	In proceeding C6258/2020 Invisible Structures Pty Ltd ACN: 065 196 401 (‘Invisible Structures’) claimed $57,945.80 plus interest from Dansan Nominees Pty Ltd ACN: 134 800 883 t/as Hyflow Plumbing (‘Hyflow’) for outstanding invoices relating to the supply and installation of the tank on two separate occasions. 
3	Specifically, Invisible Structures claimed payment of $32,719.50 for the initial supply and installation of the tank. It also claimed that Hyflow had failed to follow its post-installation instructions which following heavy rain allegedly resulted in extensive damage to the tank that required rectification. As a result, Invisible Structures also claimed $25,226.30 on a quantum meruit basis for the reasonable value of the materials and labour it provided for the second installation. 
4	Conversely, in proceeding C3924/2021 Hyflow counterclaimed against Invisible Structures for $32,357.79 plus interest for the rectification costs it incurred. Hyflow argued that the tank was not fit for purpose and that Invisible Structures had not installed it with due care and skill under the Australian Consumer Law. In addition, Hyflow asserted that Invisible Structures could not make a claim for quantum meruit due to the operation of the  Building and Construction Industry Security of Payment Act 2002 (Vic) (‘the SOP Act’). 
5	I heard the proceeding on 29 July 2021 by video conference in accordance with the applicable Tribunal Covid-19 public health response. Invisible Structures was represented by its director, Mr Jack Droomer. Hyflow was represented by its director, Mr Daniel Hoare, and also called Mr Andrew Clarke, a licensed plumber and Hyflow’s supervising foreman onsite. 
6	In determining the parties’ respective claims, I have reviewed their documentary evidence together with the oral evidence from Mr Droomer, Mr Hoare, and Mr Clarke. After the parties had completed giving their evidence and making submissions at the hearing, I reserved my decision.

Background
7	The parties generally agreed that Buxton Construction (‘the builder’) had awarded the plumbing work associated with the project to Hyflow. This work included the installation of several detention tanks designed to capture stormwater run-off. After learning that Hyflow had been awarded this work, Mr Droomer approached Mr Hoare about using the Invisible Structures product for this purpose.
8	On 16 March 2020 Invisible Structures provided Hyflow with a quotation for the supply and installation of the tank for $32,719.50. The quotation was provided on the basis that Hyflow would excavate the site and prepare the base for the tank and, after Invisible Structures had completed the installation of the tank, Hyflow would provide backfill in accordance with the specifications provided by Invisible Structures. 
9	On 17 March 2020 Invisible Structures issued a purchase order to Hyflow for the tank, followed by an invoice on 18 March 2020 for $32,719.50 advising that payment was required by 17 April 2021.  
10	On 26 March 2020 Invisible Structures inspected the sub-base prepared by Hyflow, which included some discussion of what was required and the provision of signed  site sheets. It also installed the tank in the excavated hole on this date.   On 27 March 2020 Hyflow commenced the backfill process (‘the initial/first installation’). 
11	Following heavy rain on or about 4 April 2020 (‘the rain event’) the rear of the tank floated within the surrounding soil and suffered significant damage. As a result, on 6 April 2020 the parties met onsite to discuss the damage to the tank and the need for its removal, repair, and reinstallation (‘the second installation’). 
12	Given Hyflow’s contractual obligations to Buxton, which incorporated a daily monetary penalty if the project was delayed, the parties verbally agreed to work together to expedite the reinstallation of the tank. On 7 April 2020 Invisible Structures wrote to Hyflow outlining what it understood the parties had agreed, but it did not receive a formal response from Hyflow to this correspondence. Invisible Structures also included an invoice for $1,724.80 with this letter for the additional materials it required for the second installation.  
13	On 8 April 2020 Hyflow completed the second installation of the tank with assistance from Invisible Structures. On 20 April 2020 Hyflow issued an invoice for $32,357.79 to Invisible Structures for the additional labour and material costs it had incurred in respect of the second installation. 
14	In response, on 14 May 2020 Invisible Structures issued an invoice for $25,266.30 for the labour and materials it had supplied to Hyflow for the second installation. This invoice included its earlier claim for $1,724.80. 
15	Both parties acknowledged that they failed to pay any invoice issued to them by the other, and that their dispute centred on who was responsible for the post-installation damage to the tank and the rectification costs associated with  the second installation. 
16	Invisible Structures claimed that it was entitled to be paid for the supply and  the two installations of the tank in late March and early April 2020. It asserted that Hyflow had failed to complete the backfill for the cover raft, the lid of crushed rock intended to cover the top of the tank (‘the cover raft’) as an anti-buoyancy mechanism, as specified. As a result, Invisible Structures denied any  responsibility for the post-installation damage to the tank. 
17	Conversely, Hyflow claimed that, despite following the Invisible Structures specifications and building the cover raft to the correct height, the specifications were flawed because they provided an insufficient dead weight load as an anti-buoyancy mechanism and did not provide for the tank to be partially filled with water. Hyflow argued that its responsibility was limited to excluding water ingress during the installation and, given the damage to the tank had occurred after Invisible Structures had completed its installation, the tank was never fit for purpose. 
The relevant legal principles
18	The Australian Consumer Law and Fair Trading Act 2012 (Vic) (‘the Act’) confers jurisdiction upon the Tribunal to hear and determine certain types of commercial disputes. Sections 182 and 184 of the Act enable the Tribunal to hear and determine a “consumer and trader dispute”.  Subsection 184(1) provides that the Tribunal may hear and determine a “consumer and trader” dispute, which is defined in section 182(1) expansively to include a dispute or claim arising between a purchaser or possible purchaser of goods or services and a supplier or possible supplier of goods or services in relation to a supply or possible supply of goods or services. In addition, subsection 185(4) of the Act confers jurisdiction upon the Tribunal to hear a “consumer dispute” and a “trader-trader dispute”. The definitions of both these concepts in subsection 185(4) relevantly require the dispute to be between a purchaser, or possible purchaser, of goods or services and a supplier, or possible supplier, of goods or services. 
19	The Act also confers jurisdiction on the Tribunal to hear and determine causes of action under the Australian Consumer Law, which contains consumer guarantees regarding the provision of goods and services to consumers in trade or commerce. Where there is breach of a consumer guarantee under the Australian Consumer Law that results in loss or damage to a consumer, then the consumer can sue for damages. A business will be considered a “consumer” under the Australian Consumer Law where it purchases goods or services that cost less than $40,000.00.  
20	Both parties accepted the jurisdiction of the Tribunal to hear their dispute as a “consumer and trader” dispute because their agreement related to the supply of goods (the tank) and the provision of installation services for $32,719.50. Similarly, Invisible Structures did not dispute that Hyflow was a “consumer” for the purposes of the Australian Consumer Law. However, Invisible Structures rejected the claim that it had breached either of the consumer guarantees in sections 55 and 60 of the Australian Consumer Law. 
21	Specifically, section 55 provides a consumer guarantee from the supplier of goods that the goods will be reasonably fit for any purpose the consumer told the supplier the goods were being acquired for, and for any purpose for which the supplier represents they are reasonably fit. The consumer’s purpose must be stated with sufficient to particularity to allow the supplier an opportunity to exercise its skill and judgment in making or selecting goods suited to the consumer’s purpose. The test for whether goods are reasonably fit for the disclosed purpose is assessed in terms of what a consumer could reasonably expect from the goods rather than whether the goods failed to achieve their purpose. As such, there is no requirement that the goods are absolutely fit for the particular purpose disclosed by the consumer. Correspondingly, section 60 creates a consumer guarantee that where services are provided in trade or commerce the services will be rendered with due care and skill. 
The evidence and findings
22	The parties’ dispute centred on the adequacy of the Invisible Structures specifications for an anti-buoyancy mechanism to prevent floatation of the tank within the ground, whether these requirements were properly communicated to Hyflow, and whether Hyflow implemented them correctly. 
23	Mr Droomer asserted that the specifications Invisible Structures provided to Hyflow included an anti-buoyancy mechanism. He stated that the specifications had been provided in writing and during discussions with Mr Clarke, the Hyflow site manager, and reinforced through the use of an onsite 
physical marker. Hyflow disputed these claims and argued that, even though it had implemented the instructions they received from Invisible Structures, the specifications did not provide a satisfactory anti-buoyancy mechanism.  
24	Importantly, although the Tribunal orders dated 12 May 2021 referred to the provision of expert reports, the parties preferred to rely on their respective submissions and documents, claiming that they each had the relevant expertise to address the issues raised in the proceedings. Mr Droomer gave evidence that, even though he did not have any tertiary qualifications, he had acquired extensive practical experience through his involvement in civil construction projects since 1966, including experience with the design and installation of many different types of tanks since 2002. Mr Hoare submitted that Hyflow wished to rely on Mr Clarke’s evidence as a licensed plumber with 21 years’ experience on domestic and commercial sites. As a result, there was no  independent expert evidence regarding the technical issues raised in the proceedings. 
25	Accordingly, the submissions and evidence regarding the parties’ respective claims are discussed as follows.
The relevant specifications
26	Both parties agreed that the Invisible Structures quotation dated 16 March 2020 set out the relevant specifications for the tank, including the required dimensions of the hole to be excavated by Hyflow as well as the relevant allowances for the base screed, side backfill and top cover raft. There was no dispute that Hyflow had excavated the hole to a depth of 2600 millimetres (mm) for the 1500 mm high tank, and that it had followed the specifications for the base screed and side backfill.  However, the parties disagreed as to what was meant by the following specification for the cover raft (‘the cover raft specification’):
…
Earthworks (see ALLOW below) indicative volumes only – client to calculate.
…
ALLOW FOR: Cover raft, 16.8 m3 of 20mm class 1, 300 mm deep FCR compacted to 95% Std.
The minimum total tank cover fill design must incorporate anti-buoyancy total dead load of 1 tonne per m2 x tank depth, which must include the FCR cover raft as above plus sufficient other fill to FSL (as per Invisible Structures Specification).
		…

Client’s responsibility to maintain the excavation integrity and exclude water ingress throughout the installation  period.
[Emphasis as set out in quotation]    
27	Mr Droomer gave evidence that these written instructions meant that, after covering the top of the tank with the first layer of 300 mm of fine crushed rock,  Hyflow had to place additional layers of crushed rock on top of the first layer until the backfill reached the finished surface level. Mr Droomer observed that the excavated hole was 2600mm deep, that the tank was 1524mm high, and that it also sat on 7mm of base screed. He submitted that, after allowing for variations in the finished surface level before the final concrete was poured, Mr Clarke should have been able to calculate that the excavated hole required approximately a metre of backfill to be brought to the finished surface level, particularly as they had also discussed this issue. 
28	Mr Droomer elaborated that after Invisible Structures had completed the installation on 27 March 2020, Mr Clarke started work on the cover raft and the two men discussed the required height of the backfill and whether Hyflow should fill the tank with water. Mr Droomer advised Mr Clarke that this was not necessary provided Hyflow built the backfill to approximately 100mm below the top of the 1000mm high access pipe fitted to the top of the tank, which he had marked for this purpose. Mr Droomer referred the Tribunal to the photographs he had taken and the text messages he had sent Mr Clarke at the time to support these claims.  
29	At the hearing Mr Clarke responded that he was not aware of any marking on the access pipe and that he did not provide backfill to the top of this pipe. Mr Hoare and Mr Clarke added that they did not recall being told the amount of  additional backfill required on top of the first layer of crushed rock to prevent any buoyancy issues with the tank. They noted that the quotation did not  stipulate that another 900mm of backfill was required on top of the first 300mm layer of fine crushed rock. Hyflow also relied on the signed site sheet for the “Topping Course” (or cover raft) from Mr Droomer, which Mr Hoare observed did not raise any issues with the height of the backfill provided by Hyflow.  Mr Hoare argued that Mr Droomer’s signature on this document confirmed that Hyflow had satisfactorily completed the backfill as specified on 26 March 2020. In any event, Mr Hoare submitted that Hyflow had provided 900mm of backfill for the cover raft. However, he argued that this  specification was insufficient to provide the required dead weight load for an effective anti-buoyancy mechanism.  
30	In considering the parties competing claims and evidence, on balance, I prefer Mr Droomer’s account for the following reasons.

31	The specifications set out in the quotation dated 16 March 2020 expressly stated what was required for the anti-buoyancy mechanism, including that Hyflow had to provide “sufficient other fill” to bring the backfill to the finished surface level. The cover raft clause also stated in bold text that the earthworks volumes set out in the quotation were “indicative only”, and that it was Hyflow’s responsibility to calculate what was required onsite.  In addition, Invisible Structures accepted that Mr Clarke had 21 years’ experience as a licensed plumber on domestic and commercial sites, 15 years of which had been working for Hyflow. I find it difficult to accept that a licensed  plumber with this level of experience would not have been able to calculate how much backfill was required to implement the anti-buoyancy mechanism specified. As a result, I am satisfied that the wording of the Invisible Structures cover raft specification set out sufficient information for Mr Clarke to calculate the amount of backfill required. This is especially so in circumstances where there is no dispute that he knew the height of the tank and the depth of the excavation. 
32	There are also two text messages dated 27 March 2020 that support Mr Droomer’s claim to have discussed the cover raft specification with Mr Clarke.  The first was sent at 6:44 am and the second at 8:10 am on 27 March 2020 and they respectively stated:

6:44 am 27 March 2020
Hi Andy,
Discussed tank cover raft backfill yesterday. Require 95% standard compaction of 20mm FCR – use wet mix Mtl. 
Place first 200 mm layer by spreading with excavator bucket from outside the tank. Compact with whacker or traversing the excavator. You may not achieve required 95% on first layer but will easily on subsequent layers.
NOTE: don’t put load on the 375 shaft as fragile.  

8:10 am 27 March 2020
Bring your FCR up to 100mm from top of 375mm shaft to control empty tank buoyancy. To provide permanent barricade from load 600 or 900 Conc riser half buried with star pockets in corners and bunting works well.  
[Tribunal emphasis]

It is not in dispute that the reference to the “375 shaft” in the first text message refers to the access pipe, which measured 375mm wide. Notably, Mr Hoare and Mr Clarke did not argue the veracity of the contents of these emails at the hearing. Accordingly, I give weight to the fact that the second text message specifically referred to the level on the access pipe the backfill was to reach. In addition, the text messages were sent contemporaneously with events which adds to the credibility of  Mr Droomer’s claimed discussions with Mr Clarke. 
33	I further note that the photograph Mr Droomer took at 11:32 am on 28 March 2020 lends weight to his claims that he provided a physical marker onsite regarding the level of backfill required. Mr Clarke believed the access pipe was originally higher than 1000mm and that one of his workers had cut it down, although he did not recall by how much. However, he submitted that this photograph should not be determinative of the issue. I accept that there are some limitations with the size and quality of this photograph and that it was not possible at the hearing to zoom into the photograph without distorting the image. Notwithstanding, a faint line about 100mm from the top of the access shaft can be seen in the photograph. 
34	In terms of whether Mr Droomer had marked the access pipe, I consider the photograph he took on 6 April 2020 after the tank was damaged is far less conclusive. Although  Mr Droomer submitted that the yellow arrow, he had placed on the photograph pointed to the line he had drawn on the access pipe, I am not satisfied that this is the case. The photograph shows the upended access pipe in a bed of dirt and crushed rock, but it is far from clear that the line Mr Droomer’s arrow is pointing to is a hand drawn marker rather than   dirt or crushed rock that has adhered to the side of the access pipe. Given this, I place little weight on this photograph. 
35	Hyflow also provided several photographs of the tank installed in the excavated hole prior to the side and top backfill being put in place. There was no dispute that these photographs confirm that the tank was installed in a stepped excavated hole in accordance with occupational health and safety requirements.  Notably, some of these photographs tend to reinforce Mr Droomer’s claim that Hyflow should have known that approximately 1000mm of backfill was required to bring the cover raft to the finished surface level. For example, there is a photograph of a worker standing on top of the tank a short distance away from the access pipe. I accept that the angle and distance between items in a photograph can be misleading, particularly where the 

identity and the height of the worker was not disclosed at the hearing. On the other hand, the top of the access pipe does appear to be level with the worker’s waist, suggesting the access pipe is about 1000mm high. In any event, even if the angle of the photograph with the worker is misleading, the top of the access pipe appears level with the finished surface level. Again, considering the depth of the excavated hole (2600 mm) and the height of the tank (1524mm) this strengthens the view that Mr Clarke, as an experienced plumber, should have known that about 1000mm of backfill was required to bring the cover raft to the finished surface level. 
36	Mr Clarke gave evidence that he did not recall being told to bring the backfill to 100mm from the top of the access pipe. He also denied being told that the access pipe had been marked to assist in doing so. Yet, both he and Mr Hoare insisted that they had provided backfill of 900mm because of the stepped nature of the excavation of the hole. However, given this and other discrepancies in the evidence, I do not find Mr Clarke’s evidence overly persuasive. 
37	Accordingly, having regard to the quotation, text messages, photographs, and oral evidence of the parties, on balance, I am satisfied that Invisible Structures provided Hyflow with relevant written specifications and verbal instructions for the cover raft prior to the rain event in April 2020. I find that the specifications that were provided required Hyflow to place a first layer of 300 mm of fine crushed rock followed by additional backfill as subsequent layers of at least 900mm until the fill reached the finished surface level onsite. 
Did the specifications include a satisfactory anti-buoyancy mechanism? 
38	Hyflow argued that the fact the tank had floated after the rain event meant that the Invisible Structures specifications did not provide a satisfactory anti-buoyancy mechanism for the tank. Mr Hoare and Mr Clarke both submitted that Hyflow’s responsibility under the accepted quotation was to exclude water ingress during the installation progress. However, they claimed Hyflow was not responsible for the effects of rain on the ground soil after Invisible Structures had completed its installation of the tank.  In addition, Hyflow claimed that it was industry best practice to fill the tank with water and that Invisible Structures had failed to do so in accordance with industry standards. However, Hyflow did not provide any evidence regarding what constituted best practice. Nor did it point to any industry standard that might be applicable. 
39	Notwithstanding, Mr Clarke stated that, in his experience,  detention tanks that were filled with water did not float within the ground after it rained. As a result, he believed the Invisible Structures specifications were flawed because they did not require the tank to be filled with water post installation. Again, Hyflow did not provide any expert report to this effect. In addition, apart from Mr 

Clarke, Hyflow did not call any expert witnesses to give evidence in support of these claims. Nor did they provide any technical or other material from any regulatory body or an alternative supplier that might indicate the features of a satisfactory anti-buoyancy mechanism for a detention tank.  
 
40	In assessing what weight to give Mr Clarke’s evidence I acknowledge that he is a licensed plumber with 21 years’ experience across domestic and commercial sites. I also accept that he has relevant experience in relation to the installation of detention tanks from other suppliers. However, no evidence was led as to Mr Clarke’s qualifications to comment on any technical engineering requirements for a satisfactory anti-buoyancy mechanism for detention tanks. In addition, Mr Clarke had been an employee of Hyflow for 15 years at the time of the hearing. The parties further agreed that he was the Hyflow site foreman responsible for overseeing the work that implemented the Invisible Structures specifications. As such, Mr Clarke is not an impartial witness. 
41	I have also considered Mr Clarke’s evidence that Mr Droomer had admitted to him that there had been other prior occasions when the anti-buoyancy mechanism specified by Invisible Structures had failed. Mr Clarke claimed that this had included a detention tank at a sports oval that was twice the size of the tank in this dispute. 
42	Mr Droomer did not deny there had been occasions when an underground tank installed by Invisible Structures had floated to the surface. He gave evidence that this had occurred on three earlier occasions, but in vastly different circumstances to the tank installed for the Basscare project. Mr Droomer gave evidence that on one occasion a serious flood water event had lifted the cover raft lid off the tank installed at a Queensland primary school. On another occasion, a tank at an aged care facility in Warwick, Queensland floated when the pipe that takes water into the tank broke and started to fill the area outside the tank with water, rather than fill the tank. The last occasion occurred when a tank in the Melbourne suburb of Gowanbrae suffered a massive flood of water before the side and cover raft backfill were completed. Mr Droomer advised that on each occasions Invisible Structures had not been held responsible for the floatation of the tank. He also denied that any tank Invisible Structures had installed at a sports ground had floated to the surface. 
43	In terms of Mr Clarke’s claims in this regard and his evidence about the anti-buoyancy mechanisms stipulated by other suppliers, included the desirability of filling the tank with water, I noted during the hearing that this type of claim and evidence has its limitations. I explained that the Courts have held that even the decisions of other Tribunal members are not binding upon a Tribunal member. This is because, whilst consistency of outcomes is desirable, the Tribunal is bound to apply the law to the facts before it, even if this produces outcomes that might appear inconsistent with earlier Tribunal decisions.  Accordingly, I consider this principle is equally applicable to Mr Clarke’s submissions to that effect.  As explained at the hearing, Mr Droomer’s evidence is the only evidence before me regarding other alleged failures of the Invisible Structures anti-buoyancy mechanism. Notably, his evidence indicated that there was a reasonable explanation for the floatation of the tank on each occasion, which was unrelated to the specifications Invisible Structures had provided to its client. Further, Hyflow has not provided any specifications for the detention tanks provided by other suppliers to the Tribunal. As a result, it is not possible to compare the specifications for the anti-buoyancy mechanism provided by Invisible Structures to those that may be available from other  suppliers. Accordingly, I give little weight to Mr Clarke’s evidence regarding these matters. 
44	In the circumstances, I find that Hyflow has not submitted sufficient evidence to support its claim that the Invisible Structures specifications for the cover raft failed to provide an appropriate anti-buoyancy mechanism for the tank. Accordingly, in the absence of such evidence, on balance, I am satisfied that the anti-buoyancy mechanism specified by Invisible Structures was satisfactory and should have been implemented by Hyflow.   
Did Hyflow implement the specifications onsite? 
45	In assessing issues of credibility, I have allowed for the fact that neither party had the benefit of formal legal representation in these proceedings. Notwithstanding, on balance, there were several inconsistencies in the evidence that did not assist me to form a positive view of Mr Hoare and Mr Clarke as witnesses and the plausibility of their claims. 
46	As noted previously, Mr Clarke stated that he was not aware of any marker on the access pipe regarding the level of backfill required for the cover raft and so he did not arrange for the backfill to be brought to the top of this pipe. Yet, both men also claimed at the hearing that Hyflow had provided 900mm for the backfill and that Hyflow was not responsible for the post installation damage to the tank because it had implemented the Invisible Structures specifications. They also pointed to the site sheet for the cover raft that was co-signed by Mr Droomer and Mr Clarke and dated 26 March 2020. Mr Hoare submitted that Mr Droomer’s signature on this document equated to a certification that  Hyflow had satisfactorily completed the backfill, as specified, on 26 March 2020. Mr Droomer disagreed.  
47	In considering this submission I note that this document stated at item 2.8.3:

Compaction of first crushed rock layer with hand operated compaction equipment to maximum achievable compaction. Compaction of subsequent crushed rock layers with hand compaction equipment to achieve 95% Standard Compaction (Australian Standard).
The words “Ok” and “No” also appeared in the corresponding ‘Comment’ and ‘Rectification Work Required’ columns respectively.
  
48	Apart from casting some doubt on the date of this document, Mr Droomer did not otherwise dispute its  contents. However, whilst accepting that the document was dated 26 March 2020, Mr Droomer believed that he had signed this document early on 27 March 2020 because Invisible Structures had completed its installation the day before. 
49	More importantly, Mr Droomer rejected the suggestion that Hyflow had completed the backfill for the cover raft on 26 March 2020. He explained that his notations on the sign off sheet simply confirmed that the first layer of crushed rock had been compacted as specified. At this point, Invisible Structures had completed its installation of the tank and Mr Droomer had also discussed the requirements for the completion of the backfill for the cover raft with Mr Clarke. In the circumstances,  Mr Droomer said he saw no need to remain onsite to oversee the completion of the backfill and he signed the  backfill for the cover raft.   
50	I consider that the wording of item 2.8.3 is open to the particular interpretation both parties have put forward. However, in determining what weight to give this document I note that Mr Droomer sent Mr Clarke text messages on the morning of 27 March 2020 about the requirements for the completion of the cover raft. This suggests that it is unlikely that Hyflow had fully completed the backfill associated with the cover raft on 26 March 2020, as it claimed. 
51	The evidence from Hyflow regarding their completion of the cover raft in accordance with the Invisible Structures was less than consistent. For example, Mr Hoare and Mr Clarke insisted that they had completed the cover raft in line with the Invisible Structures specifications, but that there were no instructions to backfill to 100mm below the top of the access pipe. Despite this claim, the text message sent to Mr Clarke at 8:10am on 27 March 2020 confirms that he was expressly given those instructions. At the hearing Mr Clarke stated that he did not remember receiving this text message. Although I understand that it might be difficult to recall this event some 16 months after it occurred, I do not accept that his failure to do so means that the instruction was not given. 

52	Hyflow also provided written submissions, including handwritten notes and a sketch diagram from Mr Clarke, that the level of backfill specified would have hampered other trades onsite. Mr Hoare and Mr Clarke reiterated this point during their oral evidence. They stated that this was because the specification would have meant that the backfill was well above the finished floor level of the site. In turn, they submitted that the concreters would have had to remove some of the backfill before undertaking preparatory work for the concrete slab. Mr Hoare and Mr Clarke added that they were concerned that if the concreters removed any excess backfill to level off the site it would compromise the integrity of the anti-buoyancy mechanism specified. 
53	Mr Droomer disagreed. He advised that any excess backfill cleared from the surface of the site would not compromise the anti-buoyancy mechanism given that the specification required Hyflow to bring the backfill to the finished surface level. He added that once the concreters finished the concrete slab, its weight would replace the removed backfill as the necessary dead load to achieve the required anti-buoyancy mechanism for the tank. Mr Droomer further noted that the specification was to bring the backfill to 100mm below the top of the access pipe, the top of which was to be made level with the finished surface level onsite. 
54	Mr Hoare and Mr Clarke insisted that it would have been far more desirable to have filled the tank with water. Mr Droomer reiterated that this was not required provided the cover raft was built as specified. He added that if Hyflow had believed that filling the tank with water was industry best practice it could have done so. In relation to the volume of water that would be required for this purpose, the parties agreed that it would have taken about three trucks of water at 18,000 litres per truck, or approximately 60,000 litres of water, to fill the tank. Mr Clarke responded that there was insufficient time for Hyflow to do so. Mr Droomer estimated it would have taken approximately 30 hours to fill the tank. If Hyflow completed the backfill for the cover raft by 28 March 2020, this was approximately a week before the rain event on 4 April 2020. Neither party suggested that the concrete slab had been poured by this date. In the circumstances, I consider that Hyflow had ample time in which to apply what it said was industry best practice and fill the tank with water.  As noted previously, Hyflow did not provide any evidence to support its claims regarding industry practice. Nor did it submit an expert report or call an independent expert to confirm that any removal of the surface layers of the backfill would jeopardise the anti-buoyancy mechanism Invisible Structures had specified. Notably, when asked at the hearing why Hyflow had opted to install the Invisible Structures tank instead of ordering from one of its usual suppliers, Mr Hoare responded that it was due to cost. Against this background, I consider Hyflow’s concern that there was possibly too much backfill required to complete the cover raft detracts from its claim to have diligently implemented the cover raft specifications.  This factor, alongside Hyflow’s reasons for not filling the tank with water despite ample time in which to do so, suggests that, on the balance of probabilities, Hyflow did not implement the relevant specification for the cover raft onsite, despite their claims to the contrary.  
55	Both parties provided photographic evidence of the site after the rain event. However, this evidence merely serves to indicate the extent of the damage to the tank, which was not denied by either party. Importantly, most of these photographs added little to the assessment of where responsibility for the damage should rest. However, there is one exception, Mr Droomer’s photograph of the site at 11:32 am on 28 March 2020 which the parties agreed shows a steel column sitting in a concrete pad at the finished surface level. The photograph also indicates that the backfill along the length of the excavated hole had not been brought up to the same level as this concrete pad on 28 March 2020. The pile of crushed rock surrounding the access pipe confirms the impression that the backfill task was still incomplete on 28 March 2020. As such, this photograph directly contradicts Mr Clarke’s oral evidence that Hyflow had completed the cover raft on 26 March 2020.   
56	Accordingly, based on the evidence before me, I find it is unlikely that Hyflow completed the backfill for the cover raft on 26 March 2020 despite the appearance of this date on the site sheet. The inconsistencies in the evidence from Hyflow together with the text message dated 27 March 2020 and the photographic evidence before me lend support to this view. As a result, I do not accept Hyflow’s claim that Mr Droomer had certified the work was finally completed on this date when he signed this document. 

The counterclaim regarding the consumer guarantees  
57	Hyflow counterclaimed for $32,357.79 plus interest  on the basis that Invisible Structures had breached the consumer guarantees in sections 55 and 60 of the Australian Consumer Law alleging that the tank was not fit for purpose and that Invisible Structures had not installed it with due care and skill.
58	There is no dispute that Hyflow stated its purpose for the tank to Invisible Structures with sufficient particularity, namely, that it required a suitable underground detention tank to capture stormwater run-off at the Basscare project in order to fulfill its contractual obligations to the builder. I also accept that it was reasonable for Hyflow to expect Invisible Structures, as the supplier, to identify a suitable tank for this purpose and to include appropriate specifications for an anti-buoyancy mechanism. 
59	At the hearing Hyflow did not raise any issues with the tank itself. Mr Hoare also advised that there had been no problems with the performance of the tank as a product since the second installation was completed on 8 April 2020. He claimed that this was because Hyflow had partially filled it with water. As a result, Hyflow submitted that the specifications Invisible Structures provided for the anti-buoyancy mechanism for the tank that did not include partially filling it with water were not fit for purpose. 
60	As noted previously, Hyflow did not provide any expert report or call an independent expert in support of these claims. Nor did it provide any material that confirmed what constitutes industry best practice for the installation of detention tanks. Likewise, it did not refer the Tribunal to any industry standard that might apply or lead any evidence to indicate the volume of water used to partially fill the tank. In the absence of such evidence, and given the findings and reasons set out in this decision, I find that the Invisible Structures specifications for the cover raft as an anti-buoyancy mechanism for the tank were satisfactory. I am also satisfied that the absence of any issues with the functioning of the tank after its second installation indicates that  the tank was fit for purpose. As a result, I find that there has been no breach of the consumer guarantee in section 55 of the Australian Consumer Law. 
61	Further, Hyflow claimed that Invisible Structures had failed to install the tank with due care and skill. Apart from stating that Invisible Structures should have filled the tank with water, and that it “otherwise failed to ensure that the tank was installed in a manner that would prevent it from floating”, Hyflow did not indicate in what respects Invisible Structures had failed to install the tank with due care and skill. Again, Hyflow did not provide any expert evidence to support these claims.
62	In terms of the evidence before me, I note that both parties acknowledged that the quotation upon which their agreement was based stated that it was the “Client’s responsibility to maintain the excavation integrity and exclude water ingress throughout the installation period.” This quotation also expressly stated that Hyflow was responsible for the earthworks, including any  calculations required to determine the volume of backfill.  Hyflow argued that its responsibility to exclude water ingress under this agreement was confined to the period during which Invisible Structures installed the tank because the quotation states “throughout the installation period”. However, I am not persuaded that this is the correct construction of this term in the parties’ agreement for the following reasons. 
63	According to the Macquarie Dictionary Online the word ‘throughout’ is defined to mean “1. in or to every part of; everywhere in; 2.  from the beginning to the end of; –adverb 3.  in every part; 4.  at every moment or point.” I note that, in addition to referring to what barricades and signage were required onsite, item 3 of the site sign-off sheet relevantly stated the following:
***IMPORTANT NOTE – THE TANK IS NOT DEEMED TO BE COMPLETE UNTIL THE FINAL FINISHED SURFACE IS FULLY CONSTRUCTED AS PER THE HEAD CONTRACTORS [SIC] DRAWINGS AND SPECIFICATIONS. 
The use of capitals in item 3 highlights the importance of this information, as does the fact that the word “not” was underlined. Given this and having regard to the dictionary meaning of “throughout”, I do not accept that Hyflow had no responsibility for any water ingress after Invisible Structures had completed its installation. On the contrary, I am satisfied that it had this responsibility from beginning to the end of completion of the tank. This included at all points in time until the final finished surface was fully constructed, which included the completion of the final concrete slab. 
64	Accordingly, on the evidence before me, I am satisfied that Invisible Structures has not breached the consumer guarantee in section 60 of the Australian Consumer Law. 
Summation 
65	For the above reasons, I am satisfied that Invisible Structures has established that Hyflow breached the terms of their agreement when it refused to pay Invisible Structures the agreed amount of $32,719.50 for the initial supply and installation of the tank. Although there are limitations in the evidence both parties presented to the Tribunal, on balance,  I prefer Mr Droomer’s account of the events of March and April 2020. Accordingly, I find that Invisible Structures provided Hyflow with satisfactory and detailed specifications in writing and verbally for an appropriate anti-buoyancy mechanism for the tank. I am also satisfied that Hyflow did not complete the backfill for the cover raft in line with these specifications, and that its failure to do so resulted in extensive and serious damage to the tank after the rain event on 4 April 2020.
66	Similarly, I find that Hyflow has provided insufficient evidence to establish that there has been any breach of either section 55 or 60 of the Australian Consumer Law in relation to the supply and installation of the tank. As a result, I am not satisfied that Hyflow has proven its counterclaim for $32,357.79 plus interest for the costs associated with the rectification and second installation of the tank. Therefore, the application in proceeding C3924/2021 is dismissed.
67	Given these findings, I am satisfied that Invisible Structures is entitled to be paid $32,719.50 under the agreement for the supply and first installation of the tank. Invisible Structures also claimed interest pursuant to statute in the application it made to the Tribunal on 11 November 2020. Subsection 184 (2)(b)(ii) of the Act gives the Tribunal power to award damages in the nature of interest from the date of the application until the date of decision. Using the current rate of 10% applicable under the  Penalty Interest Rates Act 1983, I find that the interest amounts to an additional $2,705.95.   
The claim for quantum meruit 
68	Invisible Structures also claimed $25,226.30 for the reasonable value of the materials and labour it provided for the second installation of the tank on a quantum meruit basis. This claim was set out in the invoice Invisible Structures issued to Hyflow on 14 May 2020 and included its earlier claim for  $1,724.80 for the additional materials to rectify the damaged tank. 
69	At the hearing Mr Hoare accepted that Hyflow owed Invisible Structures $1,724.80 for the additional materials, but he advised that Hyflow had not paid this amount due to its counterclaim for $32,357.79 plus interest.  Mr Hoare observed that the payment claim in the Invisible Structures invoice was issued under the SOP Act. As a result, he submitted that Invisible Structures could not make a claim for quantum meruit in respect of this invoice because it was obliged to follow the process set out in the SOP Act. Mr Hoare argued that Invisible Structures had not followed the correct protocol in securing payment for the alleged outstanding amount, and that it had also failed to respond to Mr Hoare’s attempts to resolve the dispute before the invoice for $25,226.30 became due. Notably, Mr Hoare was unable to articulate at the hearing which provisions of the SOP Act Hyflow was relying on to support these contentions. 
70	I consider the arguments regarding the SOP Act and quantum meruit to be misconceived.  The purpose of the SOP Act is to facilitate the ability of contractors or suppliers within the construction industry to get progress payments relating to construction work, or the supply of related goods and services, paid through a process that is relatively quick and inexpensive. As such, it is an alternative to a legal claim such as quantum meruit being made through a Tribunal or Court. However, the SOP Act does not prevent a party from making the type of civil claims application Invisible Structures has made to the Tribunal, even where they have referred to the SOP Act in the disputed invoice. 
71	Neither party disputed that they had agreed to work together to rectify and reinstall the tank a second time, and that they did so without reaching agreement about what amount would be paid to Invisible Structures for its labour and materials. As noted previously, Hyflow has acknowledged that it owed Invisible Structures $1,724.80 for replacement parts for the damaged elements of the tank. However, Hyflow disagreed that the sum of $25,226.30 was a reasonable sum to be paid for the goods and services Invisible Structures provided for the second installation of the tank. 
72	Mr Droomer gave evidence that the sum of $25,226.30 reflected the fact that during the second installation Invisible Structures had to undertake the same installation work it had completed for the first installation, less the amount of material recovered on site plus incidentals. He acknowledged that it would not be appropriate for Invisible Structures to make a second quantum meruit claim in respect of the invoice it had issued separately for $1,724.80 for the replacement of internal broken parts. Apart from noting that Hyflow should not be charged twice for the replacement of these parts, Hyflow did not take issue with Mr Droomer’s evidence on the costs of the replacement tank lining, geofabric and geogrid required for the second installation. Therefore, I find that the following amounts were incurred by Invisible Structures for the second tank installation:

Replacement of the tank lining 										$3,400.00 
Geofabric																	$   400.00
Geogrid																		$   200.00
Total:																		$4.000.00
73	Mr Droomer also advised that Invisible Structures had to engage four technicians to assist with the second reinstallation at a cost of $100.00 per hour per technician. He gave evidence that three technicians worked for 8.0 hours each for one day, and that the fourth technician worked for 4.0 hours, or half a day. In addition, Mr Droomer gave evidence that he charges $500.00 per site visit and that he made three site visits during the second installation. Mr Clarke did not dispute the hourly rates charged for the attendance of each technician, Mr Droomer’s site visit fee or the number of times Mr Droomer had visited the site. Mr Clarke added that he was unsure whether there were two or three technicians on site during the second installation. However, given the time that had elapsed since the second installation, Mr Clarke accepted that three Invisible Structures technicians were there for a full day, as well as another technician for half a day. Accordingly, I find that Invisible Structures incurred the following labour costs for the second installation:

Three technicians for 8.0 hours each							$2400.00
One technician for 4.0 hours										$  400.00
Mr Droomer’s 3 site visits											$1500.00
Subtotal:																$4300.00
74	As a result, I find that Invisible Structures is entitled to $8300.00 in quantum meruit for the additional goods and services it provided, as well as $1,724.80 for the replacement parts Hyflow has already acknowledged it owes. This comes to a total of $10,024.80. As Invisible Structures also claimed statutory interest in respect of this claim, I find that this comes to $829.07.   
Conclusion
75	Accordingly, in proceeding C6278/2020, and having regard to the whole of the evidence and for the above reasons, I find that Invisible Structures has established that Hyflow breached the terms of their agreement when it refused to pay Invisible Structures the agreed amount of $32,719.50 for the initial supply and installation of the tank. I am also satisfied that Invisible Structures has proven that Hyflow has not paid it $1,724.80 for the spare parts associated with the second installation. Likewise, I find that Invisible Structures has established its claim for quantum meruit in the amount of $8,300.00. In addition, I am satisfied that  an order for payment of damages in the way of interest is appropriate. Further, having regard to section 115B of the Act, and being satisfied that Invisible Structures has substantially succeeded in its claim, I am satisfied that Hyflow should reimburse Invisible Structures the application fee of $696.10 it paid in respect of its claim. 
76	Conversely, in proceeding C3924/2021, as indicated above, I am not satisfied that Hyflow has provided sufficient evidence to establish that Invisible Structures breached any term of their contractual agreement for the supply and installation of the tank. I am also not satisfied that Hyflow has established that the Invisible Structures breached the consumer guarantees in either section 55 or 60 of the Australian Consumer Law. Given these findings, I find that Hyflow has not proven its counterclaim for $32,357.79 plus interest against Invisible Structures.  Therefore, the application in proceeding C3924/2021 is dismissed.
77	Accordingly, I have made orders to this effect. As the parties were self-represented during the proceedings there is no need to reserve costs.

D. Buljan
Member

8 September 2021