Plumbing subcontracts: the risks and what to negotiate
Plumbing and hydraulic packages are split across stages (in-ground, rough-in, fit-off) with long gaps between them, which makes programme, remobilisation and staged payment the commercial pressure points. Most disputes start with a variation that was instructed on site and never written down.
AI risk report, not legal advice. The scanner gives general information about the risks in a document. It is not a lawyer, does not know your circumstances, and can be wrong. For decisions with legal consequences, get advice from a construction lawyer.
Where plumbing and hydraulic subcontractors lose money
Remobilisation priced as free
If the programme stretches and you are called back for a stage weeks later, the contract decides whether remobilisation is paid. A clause that treats return visits as included in the lump sum quietly converts delay into your cost.
In-ground and authority approvals
Authority inspections and approvals sit outside your control. Check that delays caused by the authority or by another trade's work give you an extension of time and are not treated as your default.
Wet area defects and back-charges
Leaks surface after other trades have covered your work. Broad indemnity and set-off clauses let the builder deduct remediation of everyone's work from your claim. Insist on notice and substantiation before any back-charge.
Fixture supply and substitution
If fixtures are client-selected or builder-supplied, the contract should say who carries the risk of late delivery and substitution. Without that, you wear the delay.
Three things to push for in your departures schedule
- Remobilisation for programme-driven return visits paid as a variation
- Written notice and evidence before any back-charge or set-off
- Extension of time for authority, inspection and other-trade delays
The free scanner finds these clauses in your actual contract in about two minutes and writes the departures schedule for you.
What the Index says
Live figures from the Australian Subcontract Index, 90 real subcontracts. The Index holds only 4 plumbing contracts so far, under the 10-contract threshold, so these are national figures across all trades. Nothing under 10 contracts is ever shown.
Plumbing subcontracts by state
Plumbing subcontracts: common questions
Should a plumbing subcontract pay for coming back to site?
It should if the return is caused by the builder's programme rather than your sequence. Price the stages you expect, then make sure the contract treats extra return visits, caused by others, as variations.
Do plumbing and hydraulic subcontractors have payment rights that override the contract?
Yes. Every state and territory has a Security of Payment Act that lets you make a payment claim and get to adjudication quickly, and several states cap how long payment terms can be. The state pages below set out each one.
Is the scanner free?
Yes. No account, no card. Upload the subcontract and the full report appears in about two minutes. General information, not legal advice.