Most QLD builders inherit a build contract template that has nothing specific to say about solar. When solar is added as a selections-sheet inclusion, the existing template can quietly leave four risks unaddressed: scope ambiguity, warranty cross-contamination, contractor allocation, and homeowner-handover language. Each of those, left unhandled, eats into your inclusion margin or pulls your team back into post-handover service calls that should never have been your problem.
This is not a "talk to your lawyer" article — your lawyer will draft the legal language. It's a guide to what should be in that language, framed for a builder who has just decided solar is going to be a margin line on every spec.
1. The inclusion clause
The simplest version: include the solar package by name, by kW size, and by component-tier. Don't list specific brand-and-model pairs in the contract — those change. Do specify the tier so the buyer can't argue you owe them a different brand if a manufacturer changes mid-build.
Recommended language pattern:
"The Builder shall supply and arrange installation of a [6.6 kW solar package / 6.6 kW solar plus 9.6 kWh battery / 10 kW solar plus 9.6 kWh battery and EV charger]. Solar PV components shall be CEC-approved Tier-1 panels, CEC-approved string or hybrid inverter, and CEC-approved battery (where included). Specific manufacturer and model selection shall remain at the Builder's discretion."
That last sentence does the heavy lifting. It pre-empts the homeowner who arrives at handover saying "I wanted the LG panels I saw at the Springfield expo." LG isn't in the contract; Tier-1 is.
2. The warranty assignment clause
Solar warranty calls are the single biggest hidden cost of bundling solar into a build. Inverter faults, monitoring app problems, panel hot-spotting, communication-card replacements — these come up in the first 12-36 months at meaningful rates. If your contract is silent on who handles them, the homeowner phones you, your service team triages them, and the install partner gets paid to fix it. You eat the coordination cost.
Recommended language pattern:
"All warranty obligations relating to the solar PV system, including panels, inverter, battery (where applicable), workmanship, and grid-connection compliance, shall transfer directly from the solar contractor to the Owner at Practical Completion. The Owner acknowledges that warranty service for the solar system shall be obtained by contacting the solar contractor directly using the contact details provided in the handover compliance pack."
Two functions here: it transfers the warranty out of the build contract, AND it tells the homeowner where to call. That second function is what actually keeps your phone from ringing — without it, even with the warranty legally elsewhere, the homeowner's first instinct is to call the builder.
3. The contractor allocation clause
Some buyers, particularly knockdown-rebuild buyers and luxury custom builds, will want to bring their own solar provider. If you've priced solar as an inclusion, that's now a conflict — your inclusion price subsidises the rest of the package, and a buyer-specified alternate provider unwinds that.
Recommended language pattern:
"The Owner shall not engage an alternative solar contractor for the works covered by this contract without the Builder's written approval. If the Owner wishes to substitute the solar package, the Builder shall provide a credit equal to the wholesale cost of the included solar package against an Owner-managed substitute, with all integration, scheduling, and grid-connection costs becoming the Owner's responsibility."
The credit-equal-to-wholesale framing is critical. You're protecting the margin layer of the inclusion (which is yours), while letting the buyer choose if they really insist. Most don't, once they understand the credit only covers the trade cost.
4. The compliance pack clause
You need the compliance pack to be the Builder's deliverable to the Owner — not an open-ended obligation. Specify what's in it, when it transfers, and what triggers Practical Completion in solar terms.
Recommended language pattern:
"Practical Completion in respect of the solar PV system requires: (a) Energex (or other applicable grid distributor) connection approval; (b) Electrical safety certificate; (c) STC rebate processing receipt; (d) Manufacturer warranty registration confirmations; (e) Installer commissioning documentation. The Builder shall provide these documents to the Owner in a single compliance pack at handover."
This clause is short but does two things. It defines what "complete" looks like for solar — your install partner can't drag the project tail by being slow on STC paperwork. And it caps your obligation: once those five items are delivered, you're done.
5. Pricing and payment milestone clause
If you're using progress-claim payments, decide where the solar component sits. The default-without-thinking is to lump it in with "Practical Completion." That works but pushes a chunk of your trade-cost outlay to the back of the project, which is hostile to your install partner's cashflow if you have hundreds of homes in flight.
Better is to align solar with the Lock-Up or Fixing stage, paid in proportion to the install-and-commission split (e.g., 70% on roof-on solar install, 30% on final-fit commissioning at handover). Trade Solar's standard terms are designed around this. Other providers vary; clarify before you sign.
What this all looks like together
A complete solar inclusion in a builder contract is five clauses: inclusion scope, warranty assignment, contractor allocation, compliance pack, and progress-payment milestone. Each one removes a specific failure mode that would otherwise cost you money or time after handover.
None of this is exotic. If your existing contract template has been used for kitchens or for ducted air conditioning, the clause structures already exist — you're adapting language, not inventing it.
What Trade Solar provides on the inclusion side
We supply a builder reference pack with: package spec sheets, sample inclusion language for selections sheets and build contracts (drafted by an Australian construction lawyer for general use; review with your own counsel before adoption), warranty-assignment template wording, and a template homeowner-handover letter explaining the solar contact path. The pack is provided to builder partners on request — it's part of the price-sheet release we send when you onboard.
Disclaimer: this article is general guidance, not legal advice. Build contract drafting in Queensland is governed by the Domestic Building Contracts Act 2000 and associated regulations. Any contract clause should be reviewed by your own legal advisor before use.