
6 minute read
Design Work by Plumbing Subcontractors
Plumbing subcontractors often engage in a certain amount of design work, whether or not the subcontract specifically refers to that being part of the scope of works.
There are various matters to consider and be aware of when it comes to undertaking design work.
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Residential projects
For residential builds, often there will not be a detailed plumbing design available to the plumbing subcontract that specifies precisely how each part of the plumbing works is to be installed / constructed.
Therefore, even if the subcontract does not specify that the scope includes design work, often a reasonable amount of design work is required.
Where a builder seeks to engage a plumbing subcontractor, it is important that, before any subcontract is agreed, the plumbing subcontractor obtains whatever plans and specifications have been prepared (possibly by the builder or an engineer) and determines the extent to which further design work is required.
Where a substantive amount of design work is required:
• It is important to discuss with the builder what the process will be with respect to finalising the design.
• If the builder indicates that the design work will be completed without the plumbing subcontractor having to be substantively involved, then a plumbing subcontractor should ask for more details to be provided so that they can accurately quote for the work.
• If the builder indicates that the plumbing subcontractor is to substantively finalise the design themselves, then it is important that the plumbing subcontractor confirm what design outcomes the design is required to achieve. Also, it is a good idea to ensure that the scope of the design work is clearly set out in the subcontract (although it is often the case that subcontracts for residential builds are quite brief).
Where the plumbing subcontractor is expected to provide a quote with respect to undertaking substantive design work and installation / construction work, it can be difficult to quote for a job where significant amounts of the design detail are not finalised.
Commercial projects
In commercial projects, particularly larger commercial projects, it is often the case that a hydraulic engineer will be involved. The hydraulic engineer may be engaged by the principal or, where the head contract is a design and construct contract, the head contractor.
Where a head contract is a design and construct contract, the head contractor may, instead of engaging a hydraulic engineer, seek to engage a plumbing subcontractor pursuant to a design and construct subcontract. In that case, the head contractor is relying solely on the plumbing subcontractor with respect to the design work.
Alternatively, the head contractor might engage a hydraulic engineer and also engage a plumbing subcontractor pursuant to a design and construct subcontract. In that case, both the hydraulic engineer and the plumbing subcontractor concurrently have design obligations to the head contractor.
Where the plumbing subcontractor is engaged pursuant to a design and construct subcontract, the plumbing subcontractor may decide to undertake the design work in-house. Alternatively, the plumbing subcontractor could itself engage a hydraulic engineer.
Given the various possible permutations, it is important that each party is clear on what its obligations are. For example, if the head contractor has engaged a hydraulic engineer and, in addition, engaged the plumbing subcontractor pursuant to a design and construct subcontract, it is important that the contracts are clear as to what design work each party is expected to undertake.
Where the head contractor does not engage a hydraulic engineer and simply engages the plumbing subcontractor pursuant to a design and construct subcontract, all the design responsibilities fall on to the plumbing subcontractor.
This may be a cost saving exercise by the head contractor. In that case, the plumbing subcontractor needs to be particularly aware of the design objections and its design responsibilities, which should be clearly set out in the subcontract.
The problems referred to above with respect to quoting for residential work where the design is not complete also apply to design and construct contracts in commercial projects.
Defective Design Work
Where the design work by a plumbing subcontractor is defective, there may be express terms in the subcontract that have been breached. For example, there may be a term that states that the design is fit for purpose.
Even when a contract is vague or silent as to there being a design component, but where design work is undertaken in some form by the plumbing subcontractor, defective design work may still be a breach of contract. This is on the basis that, regardless of the precise wording of the subcontract, the works included some design works, and there is a duty that work under a contract be undertaken with due care and diligence.
Where defective design work by the plumbing subcontract amounts to a breach of contract, and where that breach causes the builder or head contractor loss and damage, the plumbing subcontractor will generally be liable for that loss and damage.
If the defective design work was undertaken by a design subcontractor engaged by the plumbing subcontractor, while the plumbing subcontractor may be liable to the builder or the head contractor, the plumbing subcontractor may have a claim against the design subcontractor. If the defective design work was partly the fault of the plumbing subcontractor and partly the fault of, for example, a hydraulic engineer engaged by the head contractor, then the plumbing subcontractor may be concurrently / jointly liable to the head contractor. Each party may be deemed to be liable for a percentage of the loss, depending on their respective levels of fault.
Insurance
Where a problem is caused by defective design work, an insurance policy that responds to installation / construction defects may not apply.
A plumbing subcontractor that undertakes design work should consider obtaining professional indemnity insurance that applies to defective design work.
There are insurance policies that relate specifically to design and construct contractors that provide cover for defective design work.
Charles Moran
Special Counsel
Lynch Meyer Lawyers
Ph: 8236 7654 Email: cmoran@lynchmeyer.com.au
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