Two sets of rules decide when money changes hands, and they have to agree. Queensland law, in schedule 1B of the QBCC Act, caps the deposit on a home building contract at 10% between $3,300 and $20,000, 5% at $20,000 or more, and 20% where more than half the contract value is work done off site, which is most modular homes. After the deposit every progress claim must relate to work done on the site and be no more than its value; the QBCC's example is that a builder cannot claim past 50% of the price, deposit included, until half the work on site is done. A lender then adds its own schedule, inspected before each payment. Westpac's published rule is a first stage of at most 20%, no middle stage above 35% and at least 10% held for completion.
The law's side
| Rule | What schedule 1B says |
|---|---|
| Deposit | 10% on a contract over $3,300 and under $20,000; 5% at $20,000 or more; 20% where off-site work is more than half the contract value. The home warranty premium is inside the deposit |
| Progress claims | Each must relate to progress on site and be no more than the value of the work it covers. Claims at regular intervals need evidence of the work done in the period |
| Paying early or over | Reduces what the Queensland Home Warranty Scheme will pay if the builder fails. The QBCC's advice: never pay more than the contract says or before it is due |
| Variations | In writing before the work, with the price change and when it is paid; no payment for a variation before its work starts |
| Final claim | Due at practical completion, after the walk-through and the defects document |
The 20% exception is the modular clause. The QBCC's own examples of off-site work are made-to-measure kitchens, windows, sheds and cladding; a home built in a factory is the clearest case, which is why a modular contract can lawfully ask for more up front than a site build.
The bank's side
A construction lender pays the builder, not the owner, after a valuer confirms each stage. Westpac's guide caps the deposit and base stage at 20%, no single middle stage over 35%, and a minimum 10% for practical completion, and gives a five-stage example of 20, 20, 30, 20 and 10. Any schedule outside those bands goes back to the bank for approval. A maker's schedule that asks for 40% at frame or 90% before delivery does not fit, and the gap is the owner's to fill from cash or equity unless the lender funds off-site work, as Commonwealth Bank does for prefab within its limits.
Two contracts, two schedules
A modular job usually has a sale contract with the maker and a building contract with the installer. The maker's deposit and stages follow the sale contract and the 20% rule where the maker is the licensed builder; a maker that only sells the home is not under schedule 1B at all, and its schedule is whatever the sale contract says. The installer's deposit is capped at 5% on an install over $20,000 and its claims follow the piers, the crane day and the connections. A lender sees one project and wants one schedule, so line the two up on paper before anyone signs, and ask the maker to show where its payments sit against delivery.
A schedule that fits a modular install
- Deposit on the install contract: 5%.
- Footings inspected and cured: the piers and the set-out.
- Crane day: the home on its piers, levelled and tied down.
- Connections: plumbing, drainage, electrical, stormwater.
- Practical completion: the final inspection, the defects document, at least 10% held to here.
Queensland building contracts, clause by clause goes through the deposit, the cooling-off period and the variation rules in full.
See it for your block
- Install cost calculator, bucket by bucket
- Queensland building contracts, clause by clause
- How to read a building quote
Questions people ask next
What deposit can a builder take for a granny flat in Queensland?
Under schedule 1B of the QBCC Act, 10% on a contract between $3,300 and $20,000, 5% at $20,000 or more, and 20% where more than half the contract value is work done off site, which covers most modular homes. Paying more reduces home warranty protection.
How do progress payments work on a construction loan?
The lender pays the builder in stages after a valuer confirms each one. Westpac's published guide caps the first stage at 20%, no middle stage above 35%, and holds at least 10% for completion. A contract schedule outside those bands goes back to the lender for approval.
Can a builder claim for crane day before the crane has been?
No. Each progress claim must relate to work done on the site and be no more than its value. The QBCC's example is that a builder cannot claim past 50% of the price until half the work on site is done.
- QBCC, deposits and progress payments (caps, the 20% exception, claims relative to work done), read 16 October 2026
- Queensland Building and Construction Commission Act 1991, schedule 1B (deposits, progress payments, variations), read October 2026
- Westpac, guide to residential construction loans (stage percentages), read 16 October 2026
- Commonwealth Bank, prefabricated homes (off-site progress payments), read 16 October 2026
- QBCC, who pays the home warranty premium (inside the deposit), read October 2026