Your building contract decides what you get, what it costs, what happens when things go wrong and who pays. The builder writes it, so it's written to protect the builder. The good news is that you can negotiate it, and the best time is before you sign. After that, your leverage drops sharply.
Here's what's in a Queensland building contract, where there's room to move, and the rules that protect you whether you negotiate or not.
C4 - Asking the Right Questions Checklist
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Last updated 22 Oct 2026 · Revision 2 · Free updates for life
Checklist Type: Minor
Form Factor: Fillable, print-ready PDF (A4, 20 pages)
When to use: Choosing a builder (before you pay a deposit or sign)
70 questions and checks for every builder on your shortlist, from the licence search at your desk to a visit to one of their current sites. Compare like for like and choose your builder with confidence before you pay a deposit.
What's in a home building contract
A good contract should clearly cover:
- Scope of work. The plans, specification and every inclusion. If it isn't written down, assume it isn't included.
- Contract price and payments. The price, the progress payment stages and the deposit.
- Provisional sums and prime cost items. Allowances for work or items not yet fully priced, like site works or tapware. These are where many budget blowouts start. Low allowances make the price look good now and cost you later.
- Time. The start date, the number of days to practical completion, and how extensions of time are handled.
- Variations. How changes are requested, priced and approved, and how they affect the timeline.
- Defects. How defects are reported and fixed after handover.
- Disputes. The process, usually starting with negotiation and moving through the QBCC or courts.
- Termination. When either party can end the contract and what happens if they do.
- Inclusions and exclusions. Exactly what's in and what's out, from appliances to driveways and landscaping.
- Practical completion and handover. How the final inspection works and how outstanding items are dealt with.
Queensland rules that protect you
Some things aren't up for negotiation, because the law sets them. For domestic building contracts of $20,000 or more:
- Deposit: the builder can't take more than 5% of the contract price (10% for contracts under $20,000).
- Cooling-off period: you have 5 business days after you receive a signed copy of the full contract (including plans and specification) and the QBCC Consumer Building Guide. Use it to have the contract reviewed. If you withdraw, you can be charged $100 plus the builder's reasonable out-of-pocket expenses.
- Defects period: the QBCC standard new home contract gives a 12-month defects period from practical completion (General Condition 29.1).
- Home warranty: the QBCC Home Warranty Scheme covers non-structural defects that appear within 6 months of completion (lodge within 7 months) and structural defects for 6 years and 6 months.
If a builder's contract seems to give you less than this, ask why, and get advice.
When you have the most leverage
Before you sign
This is the big one. Everything is still on the table: price, inclusions, allowances, the build time and the contract terms themselves. Once you've signed, every change becomes a variation, priced by the builder.
When the market is slow
When work dries up, builders are hungrier. End of financial year and quiet periods can bring incentives, better inclusions or more flexibility on price. In a busy market, expect less give.
When the home is already built
Builders who've built a home on spec want it sold. There's often room to move on price or inclusions.
When you're early in a new estate
Builders want sales moving in a new estate and may offer better pricing or upgrades to the first buyers.
What you can negotiate
- Price and inclusions. Free upgrades are often easier to get than a lower price, because they cost the builder less than they're worth to you.
- Provisional sums and prime cost allowances. Ask for realistic allowances, or better still, fixed prices for site works once the soil test and survey are done.
- Site costs. Make sure they're based on a soil test and contour survey, not a guess.
- Build time. Ask for a realistic, specific number of days to practical completion.
- Variation pricing. Ask what margin the builder adds to variations, and get it in writing.
- Payment stages. Make sure each payment matches work actually completed.
The challenges
Standard contracts. Most builders use HIA, Master Builders or QBCC template contracts, and many won't change the general conditions. You can still negotiate the price, specification, allowances and special conditions.
Production builders are less flexible. Volume builders sell set designs at set prices. You'll have less room to customise, but you can still push on inclusions and allowances.
The builder's preferred lender. Builders sometimes offer incentives if you use their preferred broker or lender. Compare offers from other lenders. Brokers are often paid commissions, including trailing commissions, so make sure you're happy with the terms before you agree.
The fine print. Contracts are long and full of legal language. The parts that bite are usually the allowances, extension of time clauses and exclusions.
Delays. Weather, labour shortages and supply problems all cause delays. Understand how the contract handles extensions of time, and whether any delay damages apply if the builder runs late.
Hidden costs. On top of the build contract, budget for things like site costs, connections, driveways, fencing, landscaping, window coverings, and on any land purchase, transfer duty and conveyancing.
How to negotiate well
- Do your research. Compare several builders with like-for-like specifications, not just headline prices.
- Ask the right questions. Our C4 Asking the Right Questions checklist (above) is built for exactly this.
- Get the contract reviewed. Have a construction lawyer or independent building consultant review the contract, plans and specification before you sign. Expect to pay around $2,500 to $5,000 for a lawyer's review. It's small money against the cost of a house.
- Check who people work for. If you use a buyer's agent, ask who pays their commission. If it's the builder, they aren't working for you.
- Ask about incentives. If you don't ask, you won't get.
- Be prepared to walk away. If the terms don't suit you, there are other builders. Walking away also tells you how keen the builder really is.
Tools for managing the contract
Once you're building, keep every document, variation, invoice and email in one place. Builders use software such as Procore, Mastt and Zoho Contracts to manage contracts, variations and payments. As an owner, a well-organised folder and a variations register will do the job.
FAQs
Can I negotiate the base price?
Often, yes, especially in a slow market or early in a new estate. Upgrades and inclusions are usually easier to win than a lower price.
Can I change the floor plan after signing?
Usually, but it's a variation and will cost you money and time. Finalise the design before you sign.
Is my deposit refundable?
If you withdraw during the cooling-off period, you get your deposit back less $100 and the builder's reasonable out-of-pocket expenses. After that, it depends on the contract terms.
Do I have to use the builder's lender?
No. Compare offers from other lenders, even if the builder offers incentives.
Custom builder or production builder?
Custom builds give you more control but usually cost more and take longer. Production builders offer lower prices with less flexibility.
Further reading
Understanding Reasonably Foreseeable Costs in ContractsIn construction contracts, the term “reasonably foreseeable” is often used to describe events or costs that could have been predicted by a reasonable person. This blog post explores what reasonably foreseeable means in terms of contract costings and how it can impact the construction process.
Smoothing Legal Bumps with LawPathLegal hurdles can often be challenging for any business. In this article, we share our personal encounter with LawPath and how it helped streamline the legal aspects of our construction business, from drafting contracts to staying compliant.
Understanding Variations in Residential ConstructionVariations in residential construction often lead to disputes due to “grey variations”—terms understood by builders but unclear to clients. Common examples include edge protection and rock removal. Builders should transparently incorporate foreseeable costs into contracts.
A Crash Course in Australian Standards for New HomeownersCongrats on your new home! Understand Australian Standards for safety and compliance - they’re the law. Get a crash course to ensure your investment’s security.
The Importance of Contract Administration in Home BuildingBuilding a dream home? An experienced contract administrator is your advocate, ensuring that every detail aligns with your vision. From overseeing plans to resolving issues, discover how they can turn your construction journey into a smooth adventure.
Essential Questions Before Signing a Home Building ContractBefore entering a home building contract, ask yourself vital questions about land ownership, site conditions, financial readiness, and contract specifics. This ensures you are prepared for any challenges, making the building process smoother and avoiding costly surprises.
