COOPER & OXLEY GROUP PTY LTD -v- KOITKA [2026] WASC 4 (15 January 2026)

1. The adjudicator failed to perform his functions under s 38(1)(a) of the BCI Act in that he failed to consider in his determination of the amounts owed by Cooper & Oxley to Caledonia the relevant material facts that Cooper & Oxley had:

(a) terminated the contract pursuant to cl 36.7 of the construction contract;
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> (b) the rights contained in cl 36.8 of the construction contract;
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> (c) rights of set-off pursuant to cl 17.10 of the construction contract which included entitlements by reason of the termination of the construction contract.

1. The adjudicator failed to perform his functions under s 38(1)(a) of the Act in that he failed to have any, or any proper, regard to Cooper & Oxley's entitlement to set off the sum of $62,243.97 (excluding GST) in respect of backcharges, debts due and set‑off.
2. Ground 1 is predominantly concerned with the application of specific clauses of the contract, namely cl 17.10, 36.7 and 36.8, to the matters that were before the adjudicator. Ground 2 is predominantly concerned with set‑offs for backcharges, defect remediation and outstanding debts due, that Cooper & Oxley says it made against Caledonia's claim.

1. Section 3(1) of the BCI Act states that its object is:

... to provide an effective and fair process for securing payments to persons who undertake to carry out construction work, or to supply related goods and services, in the building and construction industry.

(a) giving those persons a statutory entitlement to progress payments; and

(b) establishing an expedited procedure for making claims for progress payments, for responding to those claims and for the adjudication of disputed claims; and

1. Part 2 div 2 of the BCI Act provides that a contractor is entitled to receive progress payments for work, goods and services carried out by it.[4] The right to a progress payment arises irrespective of whether the contractor is entitled to progress payments under the relevant construction contract.[5]
2. Where the contract does provide for the payment of progress payments, the amount which the contractor is entitled to is the amount calculated in accordance with the contract.[6] If the contract does not provide for the progress payments, then the contractor is entitled to an amount that is calculated:[7]

... on the basis of the value of construction work carried out or undertaken to be carried out, or of related goods and services supplied or undertaken to be supplied, by the person under the contract.

1. Section 19 of the BCI Act sets out the mechanisms by which the work is to be valued in the scenarios where the contract provides for a progress payment, and where it does not. Section 19(1)(a) provides that if the contract provides for the manner of valuation, the work must be valued in accordance with the contract.
2. Part 3 div 1 of the BCI Act sets out detailed procedures for the making by a contractor of a progress payment claim, and for the response to that claim.
3. Pursuant to s 23(6), if a contract is terminated, a payment claim may be made on or after termination and within the time prescribed by the section, which in this case is six months after the construction work was last carried out. Further, pursuant to s 23(8)(b), a progress claim can include an unpaid amount that has been the subject of a previous payment claim.
4. Section 25(1) of the BCI Act permits the respondent to a claim to respond by giving a payment schedule to the claimant. This must be done by the earlier of the time required by the contract, or 15 business days after the progress claim is made.
5. If a payment schedule is provided, s 25(2) requires that it must, amongst other matters, indicate the amount of any payment that the respondent proposes to make, or indicate that the respondent does not propose to make any payment. If the respondent proposes to pay an amount less than that claimed, or no amount at all, s 25(3)(a) requires that the payment schedule indicate why that is so.
6. Where the respondent to the claim does not respond within the required timeframe, they become liable to pay the claimed amount upon the due date for the progress payment to which the progress payment claim relates.[8]
7. The respondent to a claim may use a claimed set-off as a defence to all or part of the amounts claimed in the progress claim.[9]
8. Part 3 div 2 provides for the adjudication of payment disputes. In very general terms it provides for the appointment of an adjudicator to determine the dispute. An adjudicator is an individual registered by the Building Commissioner as such under pt 5 div 2 of the BCI Act.[10]
9. Section 28(1) provides that the claimant may apply for adjudication of a payment claim. Section 29(1) provides that an adjudication application must be made to the adjudicator nominated in the construction contract if there is one, or in any other case to the authorised nominating authority chosen by the claimant.
10. Section 34(1) permits a respondent to an adjudication application to give a response to it within 10 business days of its receipt. Section 34(2) provides that the response must be in writing and be in the approved form, if any. There is an approved form, issued by the Building Commission under s 114 of the BCI Act. It permits the respondent to attach documents to the response. The documents are to be identified in the form. The response may also contain submissions.
11. Section 34(3) provides that the respondent cannot include in the response any reasons for withholding payment unless those reasons have already been included in the payment schedule given to the claimant.
12. Section 38(1) of the BCI Act provides that the adjudicator must determine the amount of the progress payment, if any, to be paid by the respondent to the claimant, or must determine that no amount by way of a progress payment is payable.[11]
13. Section 38(2) sets out the matters that the adjudicator may consider at s 38(2)(a) to s 38(2)(h). The list is exhaustive, s 38(2) providing that the adjudicator may consider only those matters.
14. The matters to be considered include the relevant contract, the relevant payment claim, the response to that claim, the respondent's adjudication response and the submissions of the parties in respect of the adjudication.[12]
15. Section 38(3) provides that an adjudicator must not consider:

(b) any reasons included in an adjudication response for withholding payment that cannot under this Division be included in the adjudication response because those reasons were not included in the payment schedule;

1. The BCI Act is not intended to facilitate a final determination of claims made by way of a progress claim. Rather, the BCI Act facilitates the prompt determination of a progress claim to ensure that a contractor is not deprived of cash flow pending a final determination of claims under the contract.
2. There is similar legislation in New South Wales, which is the Building and Construction Industry Security of Payment Act 1999 (NSW) (BCI Act (NSW)).
3. The BCI Act (NSW) was recently considered by the New South Wales Court of Appeal in Martinus Rail Pty Ltd v Qube RE Services (No 2) Pty Ltd.[13] Payne JA (with whom Gleeson JA and Griffiths AJA agreed) said:
   1. The policy of the BCI Act (NSW) is to ensure that a contractor who carries out construction work for a principal receives progress payments for carrying out that work. The risk that the contractor might not be able to refund moneys ultimately found to be due to the principal after a successful action under the contract is a risk which is assigned to the principal. The clear policy of the BCI Act (NSW) is to 'pay now, fight later'.[14]
   2. The BCI Act (NSW) creates an entitlement that is to be determined informally, summarily and quickly, and then summarily enforced without prejudice to the rights of both parties to the construction contract which can be determined in due course.[15]
   3. The policy of the BCI Act (NSW) is to ensure that any person who undertakes to carry out construction work (or who undertakes to supply related goods and services) under a construction contract is entitled to receive, and is able to recover, progress payments for carrying out that work and supplying those goods and services.[16]
   4. The BCI Act (NSW) is intended to provide a speedy and effective means of ensuring cash flow to builders and trade subcontractors from the parties with whom they contract. It creates an entitlement that is to be determined informally, summarily and quickly, and then summarily enforced without prejudice to the common law rights of both parties which can be determined in due course.[17]
4. These observations apply with equal force to the BCI Act and I respectfully adopt them.
5. Further, as to the contents of a payment claim and a payment schedule, in Multiplex Constructions Pty Ltd v Luikens and Anor, Palmer J observed:[18]

A payment claim and a payment schedule are, in many cases, given and received by parties who are experienced in the building industry and are familiar with the particular building contract, the history of construction of the project and the broad issues which have produced the dispute as to the claimant's payment claim. [A] payment claim and a payment schedule must be produced quickly; much that is contained therein in an abbreviated form which would be meaningless to the uninformed reader will be understood readily by the parties themselves. A payment claim and a payment schedule should not, therefore, be required to be as precise and as particularised as a pleading in the Supreme Court. Nevertheless, precision and particularity must be required to a degree reasonably sufficient to apprise the parties of the real issues in the dispute.

1. Further, in relation to the word 'indicate' used in the BCI Act (NSW) in connection with the requisite content of a payment schedule, his Honour said:[19]

Section 14(3) of the Act, in requiring a respondent to "indicate" its reasons for withholding payment, does not require that a payment schedule give full particulars of those reasons. The use of the word "indicate" rather than "state", "specify" or "set out", conveys an impression that some want of precision and particularity is permissible as long as the essence of "the reason" for withholding payment is made known sufficiently to enable the claimant to make a decision whether or not to pursue the claim and to understand the nature of the case it will have to meet in an adjudication.

1. I respectfully adopt these observations in Multiplex in relation to the use of the word 'indicate' in the BCI Act.

1. The decision of an adjudicator is not subject to appeal. Further, an adjudication under the BCI Act is not amenable to jurisdictional review for non-jurisdictional error of law.[20] However, proceedings may be brought to the Supreme Court on the basis that the adjudicator made a jurisdictional error.[21]
2. If the Supreme Court finds that a jurisdictional error has occurred in relation to an adjudicator's determination under pt 3, the court may set aside the whole or any part of the determination.[22]
3. In Minister for Immigration and Multicultural Affairs v Yusuf,[23] McHugh, Gummow and Hayne JJ said:

"Jurisdictional error" can thus be seen to embrace a number of different kinds of error... . Those different kinds of error may well overlap. The circumstances of a particular case may permit more than one characterisation of the error identified, for example, as the decision-maker both asking the wrong question and ignoring relevant material. What is important, however, is that identifying a wrong issue, asking a wrong question, ignoring relevant material or relying on irrelevant material in a way that affects the exercise of power is to make an error of law. Further, doing so results in the decision-maker exceeding the authority or powers given by the relevant statute. In other words, if an error of those types is made, the decision-maker did not have authority to make the decision that was made; he or she did not have jurisdiction to make it.

1. As Pritchard J observed in Total Eden Pty Ltd v Charteris in respect of the Construction Contracts Act 2004 (WA):[24]

...if an adjudicator makes an error in construing, and then applying, a construction contract in order to determine the liability of a party under s 31(2)(b) of the Act, that error will not constitute a jurisdictional error.

1. Her Honour identified that the categories of jurisdictional error include 'misapprehending or disregarding the nature or limits of the decision maker's functions or powers' and 'failing to take into account a consideration that the statute required be considered or taking into account a consideration that the statute mandated be ignored'.[25]
2. Her Honour also said:[26]

A failure by the adjudicator to take into account a respondent's response to a claim, including the merits of any set off, constitutes a jurisdictional error because it constitutes a failure to take into account a matter which the Act requires an adjudicator take into account in determining the payment dispute.

1. Her Honour's observations apply equally to the operation of the BCI Act and I respectfully adopt them, subject to one qualification. The failure to take a matter into account must be of such a nature as to affect the exercise of power by an adjudicator. So, for example, if an adjudicator failed to take into account a matter that is inconsequential to the result, that would be unlikely to constitute jurisdictional error.
2. Further, an error of fact does not necessarily constitute jurisdictional error. It may, however, do so if it can be inferred from the nature of the error that there has been a failure to consider by an adjudicator.
3. In this case, the effect of s 25(3), s 34(3) and s 38(3) of the BCI Act is that Caledonia's progress claim, and Cooper & Oxley's payment schedule, set the parameters for the issues to be determined by the adjudicator, bearing in mind the passages from Multiplex that I have set out at [38] and [39] above. The requirement in s 19(1)(a) of the BCI Act that work the subject of a progress claim is to be valued in accordance with the contract, requires an adjudicator to apply the contract to the matters in issue raised by the progress claim and the payment schedule.
4. Consistently with the matters I have set out above, an adjudicator is not required to trawl through hundreds of pages of material put forward by the parties to discern what points might be raised. It is incumbent upon the parties to indicate the issues and matters that they contend the adjudicator needs to consider. This is best done in plain language. Further, if a party is represented by lawyers in an adjudication, an adjudicator is ordinarily entitled to proceed on the premise that the lawyer's submissions identify the ambit of the issues and matters that the party wishes to raise in the adjudication. In this case, lawyers acted for Cooper & Oxley in the adjudication.
5. It is helpful at this stage to describe the principal documents that were relied upon by the parties in respect of the progress claim, and in respect of the adjudication process.

1. The progress claim was constituted by a three page form dated 15 August 2024.[27]
2. It made claims as follows:
   1. under the original contract for works in respect of the driving range and external works, in the total sum of $56,503.65;
   2. for variations in respect of Variation Nos. 19 to 23 and 26 to 36, for the total sum of $161,572.83.
3. Cooper & Oxley responded to the progress claim by letter of 28 August 2024 addressed to Caledonia.[28] That letter was signed by Mr Durston and Mr Martino on behalf of Cooper & Oxley. It stated, amongst other matters, that:
   1. Cooper & Oxley had terminated the relevant contract pursuant to clause 36.7.
   2. Caledonia's entitlements were limited to those provided for in cl 36.8 of the contract, subject to Cooper & Oxley's right of set‑off in cl 17.10.
   3. Caledonia's obligations pursuant to cl 36.9 survived termination.
   4. The progress claim was not a valid progress claim.
   5. The variation claims were a repetition of previous claims, without further substantiation as required by cl 17.2, and which variation claims Cooper & Oxley had 'already considered, reviewed, assessed and communicated to [Caledonia] by way of its previous Payment Certificates'.
   6. Without prejudice to Cooper & Oxley's primary position that the progress claim was not a valid progress claim, Cooper & Oxley had assessed the claim and enclosed a payment schedule and payment certificate.
   7. Cooper & Oxley was undertaking certain rectification works and as soon as all such works were completed, it would reconcile the monies due under the contract, including by reference to set-offs under cl 17.10.
4. The payment certificate attached to the letter stated that Caledonia owed Cooper & Oxley $543.85 exclusive of tax. The payment schedule comprised:
   1. a one page document headed Payment Schedule;
   2. a three page detailed breakdown sheet; and
   3. a two page spreadsheet which set out the position in respect of the items claimed in Caledonia's progress claim. The spreadsheet was then cross‑referenced to a further 22 pages of material. I will refer to the spreadsheet as 'Cooper & Oxley's spreadsheet'. I attach it to these reasons.
5. The principal documents relied on by Caledonia in the adjudication include:
   1. an eight page application in the standard form attaching the contract;[29]
   2. the progress payment claim;[30]
   3. Cooper & Oxley's response to the progress payment claim;[31]
   4. Caledonia's submissions in support of the adjudication application;[32] and
   5. Caledonia's further submissions.[33]
6. The principal documents relied on by Cooper & Oxley in the adjudication include:
   1. Cooper & Oxley's written submissions, which attached a statutory declaration of Mr Martino made 2 October 2024 and of Mr Durston made 2 October 2024;[34]
   2. Cooper & Oxley's reply submissions;[35] and
   3. Cooper & Oxley's further submissions.[36] (The adjudicator required these submissions to address whether Cooper & Oxley had served its adjudication response on Caledonia within the timeframe stipulated in the BCI Act.)
7. As will be apparent from the footnoted references at [56] and [57] above, the adjudicator was provided with several hundreds of pages of documents by the parties, including extensive written submissions.
8. After the Determination was delivered on 16 October 2024, Cooper & Oxley then applied by way of a six page submission for the adjudicator to correct the Determination.[37] Cooper & Oxley contended that the adjudicator had not taken into account amounts that it had paid to Caledonia. The adjudicator rejected that application, stating that the corrections would require the reconsideration of the application, which was impermissible under the BCI Act.[38]

1. A significant portion of Cooper & Oxley's submissions on the review hearing were directed to the operation of cl 17.10, cl 36.7 and cl 36.8 of the contract.
2. I will set those clauses out in full:

To the extent permitted by law, the Contractor will be entitled to withhold or set-off from any monies due, or reasonably anticipated by the Contractor to become due, to the Subcontractor pursuant:

(a) to this Subcontract; and/or

(b) any other subcontract between the Contractor and the Subcontractor;

(including any Retention Amount or security) any debt, amount, claim for damages or any other entitlement (including under an indemnity) the Contractor may have against the Subcontractor.

The Contractor may for its convenience, by Notice to the Subcontractor, terminate this Subcontract at any time.

In the event of termination under clause 36.7 the Subcontractor's entitlement arising out of or in connection with the Works or this Subcontract (including the termination) shall be limited to:

(a) any amount then due from the Contractor to the Subcontractor but unpaid;

(b) an amount for the Works carried out in accordance with this Subcontract to the date of termination which is not included in a previous payment claim and which is properly payable; and

(c) the cost of goods, materials and equipment reasonably ordered by the Subcontractor for this Subcontract and which the Subcontractor is liable to accept, but only if they will become the Contractor's property upon payment (subject to the Subcontractor taking all reasonable steps to mitigate such costs).

1. The references in these clauses to the Contractor and the Subcontractor are to Cooper & Oxley and Caledonia respectively.
2. Clause 36.11 provided that cl 17.10 and cl 36.8 (amongst others) bind the parties notwithstanding the expiry or earlier termination of the construction contract.
3. The operation of cl 36.7 is relatively straightforward. It provides that Cooper & Oxley may, for its convenience, terminate the subcontract at any time. It is described as a 'no fault termination'. Caledonia contended before the adjudicator that cl 36.7 is an unfair contract term pursuant to s 23 of sch 2 of the Competition and Consumer Act 2010 (Cth). Caledonia also contended that Cooper & Oxley was not entitled to rely on cl 36.7 in circumstances where there was a bona fide payment dispute between it and Cooper & Oxley.[39]
4. The language of cl 17.10 and cl 36.8 is complex, and the operation of both provisions is not straightforward.
5. Clause 17.10 extends to other subcontracts between the parties, and to any monies that Cooper & Oxley reasonably anticipates 'to become due' to Caledonia. To the extent permitted by law, it permits Cooper & Oxley to set-off any debt, amount, claim for damages or any other entitlement (including under an indemnity) Cooper & Oxley may have against Caledonia. The use of the word 'may' in the last line suggests that it picks up potential claims, however, the criteria for a claim to meet the threshold of potentiality is not specified.
6. Clause 36.8 contains three separate sub-paragraphs. Cooper & Oxley placed particular emphasis on clause 36.8(b) and as I will explain, its position changed as to the proper construction of that clause.
7. Cooper & Oxley made limited reference to cl 17.10 and cl 36.8 in respect of its payment schedule. In its covering letter of 28 August 2024 to Caledonia, Cooper & Oxley stated that Caledonia's entitlement was limited to that provided for in cl 36.8, subject to Cooper & Oxley's right of set‑off in cl 17.10. The covering letter did not put forward a construction of either cl 17.10 or cl 36.8.[40]
8. Cooper & Oxley's written submissions in respect of the adjudication did not specifically refer to cl 17.10 or cl 36.8, and did not put forward any submissions as to how those clauses should be construed. Mr Martino's statutory declaration at paragraph 35 referred to 'set-off', and had a footnote citing cl 17.10.[41]
9. Cooper & Oxley's initial written submissions on this review addressed the operation of cl 17.10 and cl 36.8.[42] The submissions emphasised that pursuant to cl 36.8(b), Caledonia was only entitled to make a claim for works that were 'not included in a previous payment claim'.[43] In oral submissions, Cooper & Oxley's counsel accepted that interpretation of cl 36.8(b) was not correct. Specifically, counsel accepted that cl 36.8(b) would only apply to the extent the claim had been previously made in a previous payment claim and Cooper & Oxley had paid, or otherwise satisfied, that claim.[44]

Cooper & Oxley's response to the progress claim and the Cooper & Oxley spreadsheet

1. In Mr Martino's statutory declaration, he explained that he assessed the progress claim on behalf of Cooper & Oxley in the following way.
2. He assessed the value of the works that remained to be completed after Caledonia had suspended the contract, and then valued those works using a combination of rates previously provided by Caledonia and market rates.[45] Mr Martino says that in order to reconcile and close out the balance he:[46]

... certified the Subcontract Sum to 100% completion (to the value of $123,554.70) and then applied a negative variation for the amount of -$91,095 as shown on Payment Certificate 10.

1. The Cooper & Oxley spreadsheet implemented this approach by assuming that the contract works were 100% complete, notionally valuing the works to be completed and applying a credit for that notional value.
2. The approach taken was an unusual way to assess the progress claim.[47] In saying that, I do not intend to be critical of Mr Martino. It seems he thought that approach was preferable in circumstances where the works had been suspended, and the contract then terminated. As I explain below, the adjudicator determined that approach was not the correct way to assess the claim.

1. The Cooper & Oxley spreadsheet was split into several different sections, being contract works, variations, credits, backcharges, defect remediation, outstanding debts due. The notional value of $91,095 for work to be completed was included in the credits section. There was a calculation section at the foot, which resulted in the figure of negative $543.85.
2. Within these sections, the Cooper & Oxley spreadsheet had several different columns. They were item, description, value, previous % complete, previous value complete, % completed to date, value completed to date, and net total this claim. To the right of these columns was a further table headed claim assessment, which contained columns for claimed value, difference and reason.
3. Relevantly to Ground 1, the Cooper & Oxley spreadsheet did not expressly refer to payments which Cooper & Oxley says it had already made for work the subject of Caledonia's claims.
4. Relevantly to Ground 2, the backcharges section of the Cooper & Oxley spreadsheet contained items totalling $48,420.16. However, in respect of backcharges, Cooper & Oxley did not set out any amount in the column 'net total this claim', that column having a dash for each item. The defect remediation section, and the outstanding debts section, did have an amount inserted in that column, which was in red and thus reflected a claimed deduction.

1. The adjudicator commenced with some introductory observations, which it is unnecessary to set out.
2. The adjudicator found that the progress claim was not invalid as alleged by Cooper & Oxley.[48]
3. The adjudicator was satisfied the application was not too complex as to prevent him from being able to make a fair determination within the time required by the BCI Act.[49]
4. The adjudicator referred to Caledonia's contentions as to the alleged invalidity of Cooper & Oxley's termination of the contract. He found that the progress claim:[50]

... does not arise from, nor does it pertain to, a termination of the Contract itself. The claim was submitted as a progress payment, rather than a final payment claim.

...

I therefore find that the purported termination on 9 July 2024, has no bearing on determining this adjudication application.

1. This finding has quite limited import and is directed to Caledonia's contention that the termination was invalid.
2. In respect of the approach taken by Cooper & Oxley's payment schedule, the adjudicator observed and found:[51]

In assessing the payment claim as a final payment claim, [Cooper & Oxley] certified the scope of work as 100% complete and proceeded to apply deductions for unfinished scope work, purportedly resulting from the termination of the contract.

I do not accept [Cooper & Oxley's] position. As the payment claim subject to this application is not a final payment claim, I find that [Cooper & Oxley] does not have the right to make deductions for unfinished scope work in relation to this claim.

1. The adjudicator summarised in a table what he understood to be the party's respective positions.[52] That table appears to be derived from the progress claim and the Cooper & Oxley spreadsheet. The table does not refer to the amounts that Cooper & Oxley says it had paid, nor does it refer to the backcharges. It is apparent from the Determination that the adjudicator did not consider those matters to be raised by Cooper & Oxley. He did not address backcharges, nor did he specifically address the payments referred to in Cooper & Oxley's application for the Determination to be corrected.
2. Further, in assessing the variation claims, the adjudicator assessed, broadly speaking, whether Caledonia had notified Cooper & Oxley of the variation, the extent to which work had been carried out under the variation and the value of that work. The adjudicator also accepted Caledonia's position that the variations the subject of the progress claim had not been paid for by Cooper & Oxley.
3. I now turn to the grounds in support of the review.

1. Ground 1 in effect contends that the termination of the contract, and the application of cl 17.10 and cl 36.8 consequent upon termination, were material matters that the adjudicator failed to consider.
2. In respect of termination, the adjudicator found that the purported termination had no bearing on determining the adjudication application.[53] That finding was, however, directed to Caledonia's assertions regarding the invalidity of Cooper & Oxley's termination. Thus, the finding limited the scope of the matters raised by Caledonia. It did not purport to limit the scope of the matters raised by Cooper & Oxley.
3. Further, the possible application of cl 17.10 and cl 36.8 consequent upon termination should not be looked at in isolation from the circumstances of this case. In respect of Ground 1, the critical question is whether, in substance, the adjudicator had regard to those issues which fell within cl 17.10 and cl 36.8 that were brought to his attention by the parties.
4. Cooper & Oxley contends that the adjudicator did not have regard to their claimed rights of set-off, and to their claimed previous payments for the work the subject of the progress claim.
5. For the reasons set out at [93] to [106] below, termination did not alter the substance of how such matters were taken into account. Further, in the Determination, the adjudicator accepted that he needed to take into account such matters to the extent they were raised by the payment schedule. The fact that in doing so, the adjudicator did not specifically refer to cl 17.10 or cl 36.8 does not give rise to jurisdictional error.

1. Clause 17.10 set out Cooper & Oxley's rights of set-off. Clause 36.11 provided that cl 17.10 survived termination. Thus, Cooper & Oxley's right to claim a set-off was not affected by termination.
2. Further, the adjudicator accepted in the Determination that he needed to consider those matters that Cooper & Oxley had raised by way of set-off. I will give four examples.
3. First, in respect of Variation No. 30, the adjudicator found that Cooper & Oxley 'is entitled to set-off the amount of $655.55 (excl. GST) due to [Caledonia's] incorrect installation of the cog bars'.[54]
4. Second, the adjudicator referred in the Determination to Cooper & Oxley's 'right to set-off'.[55]
5. Third, the adjudicator rejected the claimed deduction for an outstanding debt due on progress claim 9 on the basis that he could find no reason in the payment schedule for the deduction. That reasoning implicitly accepts that if Cooper & Oxley had made good the claimed deduction, it should be set-off against Caledonia's claim.
6. Fourth, the adjudicator's consideration of the defect remediation claims implicitly accepts that if Cooper & Oxley had made good those claims, they should be set-off against Caledonia's claim.
7. In respect of the defect remediation claims, Cooper & Oxley submitted that the right to recover those costs comes from cl 24.5, not cl 17.10, thus it cannot be inferred from the adjudicator's consideration of such claims that he took into account Cooper & Oxley's rights of set‑off.[56] Respectfully, that submission overlooks that cl 17.10 does not give rise to a separate right of claim. Rather, cl 17.10 gives a right of set-off in respect of claims that Cooper & Oxley has, or may have, against Caledonia. That is, cl 17.10 applies to claims that arise elsewhere. Thus, the existence of such a claim is a necessary precondition to the application of cl 17.10. The clear inference arising from the Determination is that the adjudicator considered whether there were defect remediation claims for the purposes of assessing whether Cooper & Oxley had a set-off in respect of them.
8. Cooper & Oxley also contended that cl 17.10 permitted it to apply a set-off for 'potential claims',[57] and therefore the adjudicator was wrong to conclude that '[Cooper & Oxley] does not have the right to make deductions for unfinished scope work in relation to this claim'.[58] This finding forms part of, and has to be viewed in the context of, the entirety of the findings I have set out at [84] above. The adjudicator was dealing with Cooper & Oxley's approach of assuming the work was 100% complete and then deducting the notional value for the remaining work to be completed after its no-fault termination. He held that approach was wrong, as the claim was not a final claim. Even if he erred in that finding, it is an error of law in construing the contract and does not give rise to jurisdictional error.
9. In any event, Cooper & Oxley's submissions to the adjudicator did not suggest that the claimed set-offs were for 'potential claims'. Nor did Cooper & Oxley make any submissions as to how cl 17.10 should be applied to potential claims, in particular what level of specificity was required to constitute a matter being a potential claim.

1. Clause 36.8 appears designed to limit, or prevent, a subcontractor from making a loss of bargain claim consequent upon termination.
2. In its written submissions in these proceedings, Cooper & Oxley placed particular emphasis on cl 36.8(b). The written submissions said that cl 36.8(b) prevented Caledonia from making a claim for any work the subject of a previous progress claim.[59] That interpretation would result in Caledonia being unable to make a progress claim, post‑termination, in respect of work that it had not been paid for. As Caledonia's counsel pointed out, such an interpretation would likely fall foul of the provisions contained in s 111 of the BCI Act which provide that a provision of a contract is void to the extent that it is inconsistent with, or purports to exclude, modify or restrict the operation of this Act.
3. In its written submissions in reply, Cooper & Oxley submitted that the adjudicator 'excluded any consideration of the limitations on Caledonia's claim imposed by clause 36.8'.[60]
4. In oral submissions, Cooper & Oxley's counsel put forward a different interpretation of cl 36.8(b) to that contained in the first set of written submissions. Counsel said that cl 36.8(b) prevented Caledonia from making a claim for work that was included in a previous progress claim if Cooper & Oxley had previously paid for, or otherwise satisfied, the claim in respect of that work. That interpretation appears correct, however it does require additional words to be read into the clause. On that interpretation, in this case, cl 36.8(b) did not alter how claimed previous payments were to be taken into account and did not introduce any additional limitations on Caledonia's progress claim.
5. Further, Cooper & Oxley's counsel accepted in oral submissions that regardless of whether the contract was terminated, the adjudicator needed to take into account previous payments, and set-offs, raised by Cooper & Oxley.[61] Thus, termination of the contract did not alter the task before the adjudicator.
6. Cooper & Oxley did not put a submission to the adjudicator as to how cl 36.8 should be interpreted, and it was not referred to in their submissions on the adjudication. In addition, as just explained, Cooper & Oxley's position as to the interpretation of cl 36.8 has changed in these proceedings.
7. Further, the Determination reveals that the adjudicator proceeded on the basis he was required to have regard to any claim by Cooper & Oxley that it had previously paid for the work the subject of the progress claim. For example, in respect of the driving range claim, the adjudicator observed that Cooper & Oxley was not contesting that the claim had 'not been paid or confirming that the amount has been paid'.[62] Furthermore, in respect of the variations, the adjudicator made an express finding that it was reasonable to accept Caledonia's position that the variations the subject of the progress claim had not been paid for by Cooper & Oxley.[63]

1. In summary, the adjudicator's finding on termination limited the scope of the matters that Caledonia could claim. It did not purport to limit the matters that Cooper & Oxley could raise. Further, in this case, the application of each of cl 17.10 and cl 36.8 consequent upon termination did not alter how the progress claim would otherwise be assessed. As Cooper & Oxley accepted, the adjudicator needed to take into account previous payments and set-offs to the extent they were asserted by Cooper & Oxley, regardless of whether the contract was terminated. The adjudicator in the Determination also accepted that he needed to take into account such matters. There is, therefore, no failure by the adjudicator to perform his functions in respect of the matters raised by Ground 1.
2. For these reasons, Ground 1 is not made out.

1. In oral submissions, counsel for Cooper & Oxley submitted that if the adjudicator had applied cl 36.8, it would have highlighted what he needed to do in undertaking his task.[64] In doing so, Cooper & Oxley endeavoured to move away from the specific complaints made by Ground 1, in effect to put forward a contention that the adjudicator did not have any, or proper, regard to Cooper & Oxley's position regarding previous payments outlined in paragraph 24 of Cooper & Oxley's written submissions in these proceedings dated 19 March 2025.
2. The obstacle to that approach is it does not fall within Ground 1, which makes no reference to the adjudicator not having any, or any proper, regard to Cooper & Oxley's contentions.
3. Ground 1 is predicated on the basis that termination affected how set‑offs and previous payments claimed by Cooper & Oxley were to be taken into account. However, as I have explained, that is not the case, and Cooper & Oxley never suggested to the adjudicator that was the case. Moreover, Ground 1 is to be contrasted with Ground 2, which specifically refers to the adjudicator failing to have any, or any proper regard, to Cooper & Oxley's contentions regarding set‑offs.[65]
4. I do not consider that Ground 1 permits Cooper & Oxley to advance a contention now that the adjudicator did not have any, or any proper, regard to their contentions on the adjudication regarding the payment of previous claims.
5. Furthermore, I am not satisfied that Cooper & Oxley, by its payment schedule, or by its material relied upon in the adjudication, claimed that it had made previous payments in respect of the matters identified at paragraph 24 of its submissions.
6. At paragraph 24, Cooper & Oxley contends that had the adjudicator considered cl 17.10 and cl 36.8:[66]

... he would have determined that the claims for the following items had not only been included in a previous payment claim (contrary to the requirement of cl 36.8(b) of the Sub-Contract) but had also been paid by Cooper & Oxley to Caledonia:

24.1 Item 1 - Driving Range: $17,192.70;

24.2 Item 3 - External Works: $39,310.95 - of which $18,713.50 had already been included in Payment Claim;

24.3 Variation 20 - $2,392.50;

24.4 Variation 21 - $7,100;

24.5 Variation 27 - $2,520;

24.6 Variation 28 - $420;

24.7 Variation 29 - $9,444;

24.8 Variation 30 - $3,144.45 - of which $864.45 had already been included in Payment Claim 8; and

24.9 Variation 31 - $950.

(footnotes omitted)

1. Cooper & Oxley did not press the complaint in respect of Variation No. 20.[67] In respect of the opening paragraph of this submission, as I have explained, Cooper & Oxley's counsel accepted at the hearing that the making of claims that had been included in previous progress claims is not by itself contrary to cl 36.8(b).
2. Paragraph 24 of the written submissions has the following footnoted assertion in support of it:[68]

... the fourth column [in the Cooper & Oxley spreadsheet] from the left with the title 'Previous % complete' shows that prior to Payment Claim 10, Caledonia had claimed, and Cooper & Oxley had allowed, 100% of the value of that item, meaning that it had already been claimed and paid (save for the items specifically referenced in the sub‑paragraphs to para 24 above where only partial amounts had been claimed and paid).

1. This footnote accepts that an assertion of prior payment was not expressly made in the Cooper & Oxley spreadsheet. Cooper & Oxley also submitted that a reference to allowing 100% of the value previously claimed is understood in the industry to convey that a claim has been paid.[69] There is no evidence to that effect, and the adjudicator did not understand the reference to have that meaning. Also, an assertion that something has already been paid does not require any industry specific, or specialist, language to be understood.
2. Further, paragraph 24.2 of the extract set out at [116] above is footnoted with the following assertion:[70]

From Claim 9 to Claim 10 the percentage claim moved from 34% to 45% (see the 'Previous % complete" amount on page 382 of the Michael Affidavit for Item 3 and the % column under 'Claim to date" on page 373 of the Michael Affidavit), the value of this was $63,640.30 (34%) to $84,237.75 (45%), a difference of $20,597.45 yet $39,310.95 was claimed, thereby claiming $18,713.50 that had already been claimed and paid in Claim 9.

1. This assertion also requires that Cooper & Oxley's contention that it made previous payments be discerned from other matters, rather than it being expressly set out.
2. Cooper & Oxley's letter to Caledonia attaching its payment schedule said that Caledonia's claims for Variation Nos. 19 to 23 and 26 to 36 were a repetition of previous claims without any further substantiation and Cooper & Oxley had previously 'considered reviewed, assessed and communicated' that to Caledonia. The letter did not say that Cooper & Oxley had paid those claims.
3. In Cooper & Oxley's written submissions in support of its adjudication response, it submitted: [71]

Payment Certificate 10, further addresses each of:

(a) the Claimant's claims for payment (including for SoW and variations) included within PC-10;

(b) the backcharges and amounts deducted and set-off against any amounts to which Claimant may be entitled;

(c) the various variation claims repeated in PC-10, included and assessed as part of Claimant's previous payment claims and for which no further substantiation is provided, notwithstanding requests to that effect; and

(d) the issue about retention, which Respondent corrected since issuing payment certificate.

1. The submissions do not suggest that Cooper & Oxley had paid for work claimed in previous payment claims.
2. Cooper & Oxley's counsel frankly submitted that:[72]

... a problem is that there is no express reference to say, "This amount has been satisfied in this claim" in terms of in writing - so in a submission or in a statutory declaration. What is shown is that it's a description of how the matters have been assessed.

1. Mr Martino's statutory declaration identified the general approach that he had taken to assessing all of Caldonia's progress claims, stating that he:[73]

... generally adopted the following approach upon receipt of a payment claim from the Claimant:

(a) reconcile the payment claim against the previously certified amount. I often found in assessing the Claimant's payment claims that they were calculated off an incorrect previously certified amount, i.e. where we had previously made payment against a variation item, it would again be claimed in full;

1. However, this excerpt is directed to his assessment of all progress claims. It is not specific to the progress claim the subject of this review.
2. Given the extensive amount of material relied on by Cooper & Oxley in the adjudication, and the quantum of the alleged previous payments, it would reasonably be expected that an assertion the payments had been made would be set out clearly in the submissions to the adjudicator, and in the statutory declarations relied on.
3. However, from what I can discern, the first time Cooper & Oxley expressly raised the issue of previous payments was in its written submissions that sought to have the adjudicator correct the Determination by taking those payments into account. It is difficult to understand why doing so was left to a point after the adjudication had been made.
4. Ultimately, even if Ground 1 did capture a contention that the adjudicator did not have any, or any proper, regard to Cooper & Oxley's contentions regarding the previous payments, I am not satisfied that the 'essence' of that matter was raised by Cooper & Oxley's payment schedule. Nor am I satisfied that it was raised by Cooper & Oxley in the adjudication. Thus, an expanded operation of Ground 1 would not assist Cooper & Oxley in any event.
5. Given the findings I have made, it is not necessary to consider each of the specific complaints which Cooper & Oxley makes about the Determination in respect of the items set out in paragraph 24 of its submissions.

1. Ground 2 is directed to the specifics of how the adjudicator addressed Cooper & Oxley's claimed set-offs. Specifically, Cooper & Oxley contends that the adjudicator failed to have any, or any proper, regard to their claimed set-offs in respect of:
   1. backcharges totalling $48,420.16;
   2. defect remediation totalling $3,415.90; and
   3. outstanding debt due of $10,407.96.
2. I will deal with those matters in that order.

1. It is helpful to repeat what I said earlier as to what is set out in the Determination, and in the Cooper & Oxley spreadsheet, regarding backcharges.
2. The table in the Determination that summarised the parties' respective positions makes no reference to backcharges. Further, the adjudicator did not make any findings in respect of the claimed backcharges.
3. The Cooper & Oxley spreadsheet has a separate section under the heading of 'BACK CHARGES', which appears on page two. Under that heading, there were claimed backcharges in respect of six items, which totalled $48,420.16. The column on the right of the spreadsheet was headed 'Net Total this Claim'. In that column, Cooper & Oxley did not make any claim in respect of the backcharges. This is to be contrasted with the set‑offs claimed in respect of defect remediation and outstanding debts due, where Cooper & Oxley has put the amount of the claimed set‑off in the 'Net Total This Claim' column.
4. In those circumstances, it is understandable that the adjudicator did not appreciate that Cooper & Oxley claimed a set-off in respect of the backcharges. Even so, I need to determine whether Cooper & Oxley, by its payment schedule, made a claim to set off the backcharges. If it did, then there will be jurisdictional error, as the adjudicator would have failed to consider a material matter raised by Cooper & Oxley in response to the progress claim.
5. It is instructive to start with the meaning of the phrase 'backcharge'. A backcharge arises where party A has engaged party B to provide certain goods or services for payment, and party A makes a charge back to party B for some failure in providing those goods or services. Thus, a 'backcharge' is a claim by party A against party B.
6. The detail provided in the Cooper & Oxley spreadsheet suggests the items are backcharges. For example, the phrases 'Driving range retaining wall - damage to irrigation conduit' and 'Patching works carried out by plasterer'.
7. In addition, Cooper & Oxley's submissions on the adjudication application stated that its payment certificate addressed 'the backcharges and amounts deducted and set‑off against any amounts to which [Caledonia] may be entitled'.[74]
8. Mr Martino in his statutory declaration said:[75]

Against the PC‑10 claim amount I then applied and carried over back charges, scope adjustments for incomplete works, debts due and payable to Respondent pursuant to the Subcontract (and previously applied to payment claim 9 and carried over from payment claim 9) and subject to set‑off in the amount of $62,243.97 (ex GST), against any amounts owed to Claimant.

(footnotes omitted)

1. This amount of $62,243.97 is within five cents of the total in the Cooper & Oxley spreadsheet for backcharges, defect remediation and outstanding debts due of $62,244.02.
2. As I have said, it is understandable the adjudicator did not appreciate from the Cooper & Oxley spreadsheet that it was seeking to set-off the backcharges. Even so, I am satisfied that the Cooper & Oxley spreadsheet did indicate that Cooper & Oxley sought to set‑off the backcharges. I am also satisfied that Cooper & Oxley maintained that claim in its written submissions in the adjudication, and in Mr Martino's statutory declaration.
3. Caledonia in its written submissions went to some lengths to link the claimed backcharges to variations that were assessed by the adjudicator.[76] However, I do not think it can therefore be inferred the adjudicator had regard to the backcharges in reaching the conclusions that he did regarding those variations. The absence of the backcharges in the table in the Determination that summarised the parties' positions conveys that the adjudicator did not appreciate it was necessary to consider them, and that he did not do so.
4. Further, there were six claimed backcharges which represented about 22% of Caledonia's total claim. They were raised in Cooper & Oxley's submissions on the adjudication and in Mr Martino's statutory declaration. In my view, in performing his functions, the adjudicator was required to separately consider whether Cooper & Oxley was entitled to claim the backcharges as a set-off.
5. For these reasons, the adjudicator did not address a material matter raised by Cooper & Oxley's payment schedule, and did not address a material matter raised by Cooper & Oxley in its adjudication response. There is therefore jurisdictional error.
6. Ground 2 is therefore made out in respect of the backcharges.

1. The Cooper & Oxley spreadsheet had a heading 'DEFECT REMEDIATION' on page two. It claimed a total of $3,415.90 in respect of:
   1. Driving range stairs (CCS Invoice 51915) in the sum of $2,007.75; and
   2. Clubhouse threshold (CCS Invoice 51840) in the sum of $1,408.15.
2. The invoices and accompanying worksheets were attached to Mr Martino's statutory declaration.[77]
3. The adjudicator addressed this aspect of the claim at paragraphs 214 to 216 of the Determination:

Defect remediation 1 Driving range stairs:- -$2,007.75 (Excl. GST) and

Defect remediation 2 Clubhouse threshold:- -$1,408.15 (Excl. GST).

The respondent provided two invoices in their payment schedule, asserting that they relate to defect work associated with the driving range stairs and clubhouse threshold. Upon reviewing these invoices, I note that one pertains to concrete cutting, and the other to polishing.

I was unable to establish any link between the work described in the invoices and any defect attributable to the claimant or any defect raised by the respondent on the claimant, either within the payment schedule or elsewhere.

I therefore determine the amount of Defect remediation 1 and 2, in Payment Claim 10 at $0.00 (Excl. GST).

(original emphasis)

1. It is apparent from this passage that the adjudicator considered the invoices, and in doing so, recognised the need to consider Cooper & Oxley's claimed set-offs. Moreover, it is apparent the adjudicator considered whether there was a connection between the invoices and 'defect work associated with the driving range stairs and clubhouse threshold'.
2. Cooper & Oxley submits that there were emails before the adjudicator between Cooper & Oxley and Caledonia pertaining to the requisite rectification work for the driving range stairs[78] and for the exposed concrete pour at the clubhouse.[79] These emails identify the scope of the remedial work required.
3. Cooper & Oxley's submission is to the effect that it can be inferred from the rejection of the defect remediation claims that the adjudicator did not properly consider these emails.

Defect remediation claim in respect of the driving range stairs

1. It seems that Cooper & Oxley's complaint regarding the stairs was directed to the 'trip stop detail'.[80] In the final email regarding the stairs, Cooper & Oxley said that if the defects were not completed by 19 July 2024, Cooper & Oxley 'will be making plans to rectify works'.[81] The email does not identify the works that would be undertaken.
2. The adjudicator asked the right question, namely whether the work the subject of invoice 51915 was undertaken to remedy the claimed defect with the stairs. In doing so, he considered the invoice. It is not immediately apparent from the invoice and the accompanying worksheet that the work related to the defects complained of. The emails pertain to those defects, but do not descend into any material detail as to the nature of the remedial work required, or undertaken. In all of these circumstances, I am not satisfied that it can be inferred that the adjudicator did not have proper regard to the emails pertaining to the claimed defect with the stairs.

Defect remediation claim in respect of the clubhouse threshold

1. The emails relied on by Cooper & Oxley suggest that the relevant defect is that the concrete threshold for the driving range was not flush, and thus prevented a subsill being installed, which in turn prevented the installation of bi-fold doors.[82]
2. The adjudicator asked the right question, namely whether the work subject of invoice 51840 was undertaken to remedy the claimed defect. And he considered the invoice. It described the work as 'concrete cutting works'. It is not immediately apparent from the invoice that the work related to the alleged defects to the clubhouse threshold. In all of these circumstances, I am not satisfied that it can be inferred that he did not have proper regard to the emails pertaining to the claimed clubhouse threshold defect.

Final observation in relation to the defect remediation claims

1. Finally, any misunderstanding by the adjudicator as to the relationship between the reasons given by the payment schedule for these claimed set-offs, and the detail contained in the adjudication response, would not be a jurisdictional error.[83] Cooper & Oxley's complaints on this application fall very much within the realm of a merits review.

1. The Cooper & Oxley spreadsheet has a heading 'OUTSTANDING DEBTS DUE - PROGRESS CLAIMS' on page two. It claimed a total of $10,407.96 in respect of an outstanding debt due for progress claim 9.
2. The Determination addressed this matter at paragraphs 217 to 218. The heading to paragraph 217 stated 'Outstanding Debts Due 1 Outstanding debt due progress claim 09: - $10,407.96'. The Determination then states at paragraph 217:

I am not able to find any reason in the payment schedule for this deduction.

1. Respectfully, this finding is not explicable when regard is had to the Cooper & Oxley spreadsheet, and to the heading in the Determination above paragraph 217. Both make clear that the sole basis for the deduction was progress claim 9. In assessing this item, the adjudicator was required to consider progress claim 9 and determine whether it made out the claimed deduction.
2. Further, payment schedule 9 was before the adjudicator.[84] It stated that the current payment due was '($10,407.96)'. The brackets convey that Caledonia owed Cooper & Oxley that amount, which is the same amount as claimed in the Cooper & Oxley spreadsheet.
3. Accordingly, the Cooper & Oxley spreadsheet, and the additional material before the adjudicator, clearly articulated that an outstanding debt from progress claim 9 was the basis for the claimed deduction. The adjudicator did not find that progress claim 9 did not support the deduction. Rather, he found that he was not able to find any reason in the payment schedule for the deduction. In these circumstances overall, I am satisfied that an inference should be drawn that the adjudicator did not have regard to whether progress claim 9 supported the claimed set‑off.
4. Caledonia says that the adjudicator's finding reflects an error of fact that does not give rise to a jurisdictional error. That proposition may have well been correct if the adjudicator had said that he had considered progress claim 9 and it did not support the claimed debt. However, that proposition does not hold where the payment schedule makes clear that Cooper & Oxley relied on progress claim 9 for the claimed deduction, yet the adjudicator rejected the claim on the ground that he could not discern the reason given in the payment schedule for the deduction.
5. For these reasons, the adjudicator did not address a material aspect of Cooper & Oxley's response to the progress claim, and there is jurisdictional error in respect of his finding pertaining to the claimed deduction.

1. In summary, Ground 2 is made out in respect of the backcharges and the claimed deduction for progress claim 9. It is not made out in respect of the defect remediation claims for the driving range stairs and the clubhouse threshold.

1. For these reasons, Ground 1 is not made out. Ground 2 is made out in part.
2. I will hear from the parties as to the appropriate orders to give effect to these reasons, and as to costs.
3. I will make a final observation. The BCI Act envisages that the procedures relating to progress claims are carried out expeditiously, efficiently and fairly, recognising that a progress claim is an interim claim. To achieve these objectives, the parties to a progress claim need to make sure their position in respect of the claim is clearly expressed. Doing so significantly reduces the need for, and scope of, proceedings such as these, and the legal costs associated with them. It is also important to bear in mind that clarity is usually achieved by the use of plain language.

I certify that the preceding paragraph(s) comprise the reasons for decision of the Supreme Court of Western Australia.

[1] The BCI Act applied to construction contracts that would have otherwise been subject to the Construction Contracts Act 2004 (WA).

[2] Cooper & Oxley's written submissions dated 19 March 2025, pars 1 - 11.

[3] Affidavit of Kylie Simone Michael sworn 13 November 2024 (Ms Michael's Affidavit), pages 375 - 377.

[9] Duro Felguera Australia Pty Ltd v Samsung C&T Corporation [2018] WASCA 28 [35] - [36] (Martin CJ); [165] ‑ [168] (Buss P and Murphy JA).

[13] Martinus Rail Pty Ltd v Qube RE Services (No 2) Pty Ltd [2025] NSWCA 49 (Martinus). The High Court refused to grant special leave to appeal from the judgment, see Qube RE Services (No 2) Pty Ltd ABN 95320369982 v Martinus Rail Pty Limited ACN 117147645 [2025] HCADisp 171.

[18] Multiplex Constructions Pty Ltd v Luikens [2003] NSWSC 1140 [76].

[20] Perrinepod Pty Ltd v Georgiou Building Pty Ltd [2011] WASCA 217 [118] (Murphy J, Martin CJ agreeing). See also [109]. Probuild Constructions (Aust) Pty Ltd v Shade Systems Pty Ltd [2018] HCA 4 [53].

[23] Minister for Immigration and Multicultural Affairs v Yusuf [2001] HCA 30 [82].

[24] Total Eden Pty Ltd v Charteris [2018] WASC 60 [29].

[26] Total Eden [63]. See also Rodger v De Gelder [2015] NSWCA 211.

[28] Ms Michael's Affidavit, pages 375 - 377.

[29] Ms Michael's Affidavit, pages 40 - 123.

[30] Ms Michael's Affidavit, pages 124 - 126.

[31] Ms Michael's Affidavit, pages 128 - 129.

[32] Ms Michael's Affidavit, pages 145 - 247.

[33] Ms Michael's Affidavit, pages 617 - 630.

[34] Ms Michael's Affidavit, pages 249 - 609.

[35] Ms Michael's Affidavit, pages 638 - 704.

[36] Ms Michael's Affidavit, pages 706 - 712.

[37] Ms Michael's Affidavit, pages 717 - 722.

[38] Ms Michael's Affidavit, pages 724 - 725.

[40] Ms Michael's Affidavit, pages 375 - 377.

[42] Cooper & Oxley's written submissions dated 19 March 2025, pars 22 and 23.

[43] Cooper & Oxley's written submissions dated 19 March 2025, par 22.2.

[45] Ms Michael's Affidavit, page 273; par 34(c)(vi) of Mr Martino's statutory declaration.

[46] Ms Michael's Affidavit, page 273; par 34(c)(vii) of Mr Martino's statutory declaration.

[56] Cooper & Oxley's written submissions in reply dated 27 April 2025, par 27.5.

[59] Cooper & Oxley's written submissions dated 19 March 2025, par 22.2.

[60] Cooper & Oxley's written submissions in reply dated 27 April 2025, par 10.

[65] See also Cooper & Oxley's written submissions dated 19 March 2025, par 34.

[66] Cooper & Oxley's written submissions dated 19 March 2025, par 24.

[68] Footnote 20 to Cooper & Oxley's written submissions dated 19 March 2025. Footnotes 21 and 22 also pick up the concept that a reference to 'previous % complete' reflects that Cooper & Oxley had previously allowed and paid certain claims.

[70] Footnote 21 to Cooper & Oxley's written submissions dated 19 March 2025.

[71] Ms Michael's Affidavit, page 253 [16].

[73] Ms Michael's Affidavit, page 265; Mr Martino's statutory declaration par 20(a).

[74] Ms Michael's Affidavit, page 253, par 16(b).

[75] Ms Michael's Affidavit, page 274; Mr Martino's statutory declaration par 35.

[76] Caledonia's submissions dated 7 April 2025, par 37.

[77] Ms Michael's Affidavit, pages 397 - 400.

[78] Ms Michael's Affidavit, pages 526 - 534; annexure LM9 to Mr Martino's statutory declaration and referred to by him at par 37.

[79] Ms Michael's Affidavit, pages 535 - 541; annexure LM10 to Mr Martino's statutory declaration and referred to by him at par 37.

[84] Ms Michael's Affidavit, page 213, which was contained within Caledonia's documentation lodged with the adjudication application.