“Fixed price” is the phrase most Sunshine Coast homeowners want to hear, and the one most often misread. It does not mean the figure on page one can never move. It means your builder has committed to a stated sum for a stated scope, and that any movement must come through a mechanism the contract sets out and the law allows.
What does a fixed price building contract actually mean in Queensland?
Domestic building work here is governed by Schedule 1B of the Queensland Building and Construction Commission Act 1991, administered by the QBCC. Schedule 1B sets the form and content rules, and it sets them separately for each contract level, so the first question is always which level you are on.
For a level 2 regulated contract, meaning $20,000 or more, section 14 does the heavy lifting. Section 14(4) says that if the contract price is fixed, it must be stated in a prominent position on the first page of the contract schedule. Section 14(5) says that if it is not fixed, the method for calculating it, including any allowances, must be stated in the contract schedule instead.
The clause that matters most is section 14(6). If the contract price may be changed under a provision of the contract, the contract must also contain a warning to that effect and a brief explanation of the effect of that provision. Section 14(7) requires that warning and explanation to sit in a prominent position on the first page of the contract schedule as well. So a fixed price is fixed for the described scope, with every exception declared up front, on page one. If you cannot find that warning, you do not yet know what your contract says.
Which QBCC contract level applies to your project?
The QBCC advises that Schedule 1B applies only to contracts priced above $3,300 including labour, materials and GST. Above that there are two levels: a level 1 regulated contract from $3,301 to $19,999, and a level 2 regulated contract at $20,000 or more.
Almost every project we take on across Coolum Beach, Noosa and Pelican Waters is level 2. Per the QBCC, that level also requires the Consumer Building Guide before you sign, a stated date for the start of work on site or a method for determining it, a statement of the statutory warranties that apply, and a commencement notice under section 16 within 10 business days of work starting on site.
What must a Queensland domestic building contract contain?
Per the QBCC, every regulated contract must be in writing, dated, signed, and must state:
- both parties’ names, with the builder’s name and QBCC licence number as they appear on the licence;
- a description of the contracted work;
- the contract price, or the method for calculating it including the builder’s reasonable estimate;
- the date for practical completion, or how it is determined;
- a copy of any plans and specifications; and
- a conspicuous notice about your cooling-off rights.
Section 15 requires a readily legible signed copy of the whole contract, plans and specifications included, within five business days after the contract is entered into. Before signing, confirm the licence is current and correctly classed – see how to check a QBCC licence.
How much deposit can a Queensland builder ask for?
Section 33 caps deposits. Per the QBCC, before starting work on site the maximum is 10% of the contract price for a level 1 contract and 5% for a level 2 contract, with one exception: where the value of the off-site work is more than 50% of the contract price, up to 20% is allowed. Section 33(3) defines off-site work as contracted services performed somewhere other than the place the work is finally installed or constructed, which targets substantial prefabrication, not ordinary site-built work.
“Deposit” is defined broadly. Section 33(3) captures any payment for domestic building work demanded or received before the contracted services start on site, and gives an insurance premium as an example, so the Queensland Home Warranty Scheme premium counts toward the cap. After the deposit, section 34 allows no claim unless it is directly related to the progress of the work at the building site and proportionate to the value of the work the claim covers.
Is there a cooling-off period on a Queensland building contract?
Usually, yes. Under section 35(1) you may withdraw within five business days after the day you receive a copy of the signed contract. On a level 2 contract, if the Consumer Building Guide does not reach you before that copy, section 35(2) gives you five business days after the day you receive the guide, so a builder’s delay extends your window. Under section 35(3), if five business days pass from the day the contract was entered and you have received neither document, you may withdraw.
Section 36 sets limits on that right. You cannot withdraw if you and the same builder previously entered a regulated contract on substantially the same terms for substantially the same work on the same home, or if you received formal legal advice about the contract before entering it, meaning independent paid advice from a practising legal practitioner. Section 37 sets the procedure: a written notice, signed by you, stating that you withdraw and naming the section you rely on. Under section 38 the builder retains any out-of-pocket expenses reasonably incurred before you withdrew, plus $100 where you withdraw under section 35(1).
What are prime cost items and provisional sums?
These are the two allowances that most often move a “fixed” price. A prime cost item is a fixture or fitting not yet selected, or whose price is unknown at signing, for which the builder makes a reasonable allowance – tiles, tapware, appliances. A provisional sum, defined in section 10, estimates the cost of particular contracted services for which the builder, after making all reasonable enquiries, cannot state a definite amount at signing – rock removal, asbestos removal, earthworks.
Under section 26 the builder warrants that the allowance was calculated with reasonable care and skill, having regard to all the information reasonably available when the contract was entered into, including information about the nature and location of the building site. The QBCC warns that contracts with a high proportion of the price covered by allowances, for example 30% or more, carry added risk for owners. On the Sunshine Coast those sums usually attach to rock, reactive or sandy soils, retaining and access – see building on a sloping block in Queensland.
When can a fixed price legally change?
- An agreed variation. Under section 40(5) the builder must not start variation work before you agree to it in writing, and section 40(2) requires a written copy of the variation to reach you before the first of two things happens: five business days elapsing from the day you both agreed, or the variation work starting. Section 41 sets what the document must contain – a description of the variation, the date of the request, the price change or how it is calculated, when an increase is paid or a decrease accounted for, and a reasonable estimate of any delay. Section 41(3) blocks payment of an increase before the variation work starts – see building contract variations in Queensland.
- An allowance being reconciled. Prime cost and provisional sum amounts are adjusted against actual cost, up or down.
- Foundations data. Where the work requires the construction or alteration of footings or a concrete slab, or may adversely affect them, section 31(2) requires the builder to obtain the foundations data appropriate for the site before entering the contract. Section 31(8) then blocks a later claim for an amount the need for which could reasonably have been established had that data been obtained. The carve-out in section 31(3) is narrow: it applies only where the builder was not lawfully entitled to enter the land beforehand and the contract guarantees no increase in the price because of the data.
- Any other price-change provision named in the page-one warning. Read it and ask what triggers it.
Extensions of time are separate: under section 42 they move the date for practical completion, not the price.
What questions should you ask a builder before you sign?
- What proportion of this price is genuinely fixed, and what sits in prime cost items and provisional sums?
- Show me the price-change warning on page one and explain each provision behind it.
- Which contract are you using, and may I take a blank copy away to read?
- How are progress claims staged, and how do I verify each stage on site?
- Has foundations data been obtained for this site, and may I have a copy?
There is a longer list in our guide to questions to ask a builder in Queensland.
Do you need a written contract for a small job in Queensland?
Schedule 1B applies above $3,300, but the QBCC recommends recording even smaller jobs in a brief written document and publishes a free two-page Small Building Projects Contract for that purpose. The QBCC also states it is illegal to use that contract where the price is over $3,300.
Does the deposit include QBCC home warranty insurance?
Usually. The QBCC requires the builder to collect the Queensland Home Warranty Scheme premium and pay it to the QBCC within 10 business days after the date the contract was entered into, or before the work starts, whichever is earlier. It is commonly included in the deposit payable at signing, and under section 33(3) it counts toward the statutory cap.
How we handle contracts at Roebuck Concepts
We work from one office at Unit 1/18 Lomandra Place, Coolum Beach, across the Sunshine Coast and Noosa Shire. Roebuck Concepts holds QBCC company licence 15280811; director Tom Roebuck holds individual licence 15015060 and 20-plus years in residential construction. We are Master Builders Queensland members, and our Grandview project at Coolum Beach won three 2025 Master Builders Queensland Sunshine Coast Housing & Construction Awards: Home Renovation/Remodelling Project over $1 million, Best Residential Swimming Pool, and Best Use of Innovation.
Because we build under two planning schemes, Sunshine Coast Council’s and Noosa Shire Council’s Noosa Plan 2020, we scope approvals and site conditions before pricing rather than parking them in a provisional sum. Comparing contracts for a new home or a renovation? Book a consult on 0477 333 386.