Construction Loan Guide Australia 2026

Building a new home in Australia involves a different kind of home loan than buying an existing property. Construction loans pay out in stages as the build progresses, charge interest only on the drawn amount, and convert to a standard mortgage at handover. The mechanics catch a lot of buyers by surprise. This guide walks through how the product actually works, what the lender will want from your builder, and the cash-flow implications across a typical 12-month build.

How progress drawdowns work

The five-stage drawdown structure is broadly standardised across the major-bank panel, with minor variations:

1. Slab / base stage (15 to 20%): Site preparation, foundations, slab. Released after the slab is poured and the builder invoices for this stage.
2. Frame stage (20%): Wall frames, roof trusses, internal framing complete. Released after frame inspection.
3. Lock-up / enclosed (20%): External walls, windows, doors, roof on. The structure is weatherproof.
4. Fix-out (25 to 30%): Internal cabinetry, plastering, ceilings, internal doors, kitchen and bathroom rough-in.
5. Practical completion (10 to 15%): Final fittings, painting, flooring, certification. Building handover.

Each drawdown requires the builder to invoice for the stage, you to authorise payment, and the lender to send a valuer or inspector to confirm the stage is genuinely complete. The lender will not pay an invoice the inspection does not corroborate. This is a feature, not a bug; the inspection regime is what protects the lender (and you) from prepaying for work not done.

Interest during the build period

You only pay interest on the drawn-down amount during construction, not the full loan. This is the major cash-flow advantage of a construction loan over funding a build through a standard term loan. A worked example for a $700,000 build over 12 months at 6.55 per cent variable interest:

Fixed-price contracts and what lenders want

The lender\'s exposure during construction is to the build coming in over budget, the builder going under, or the build not getting finished. To manage that risk, most lenders require:

• A signed fixed-price contract with a licensed builder, with the builder\'s licence verified.
• Council-approved plans and specifications consistent with the contract.
• Builder\'s home warranty insurance (or state equivalent: HBCF in NSW, BICW in QLD, DBI in VIC).
• Construction insurance covering the build period until handover.
• Site valuation and (sometimes) builder financial review.

The fixed-price contract is the single biggest factor in approval and rate. Cost-plus and labour-only contracts are accepted by fewer lenders and usually attract a higher rate or a larger contingency requirement on top of the contract price.

Owner-builder construction loans

If you intend to manage the build yourself rather than contracting a licensed builder, your loan options narrow significantly. Most major banks decline owner-builder applications, and the non-bank lenders that accept them typically cap the LVR at 60 to 70 per cent (compared with 80 to 95 per cent for licensed-builder contracts). The lender pricing also runs 0.5 to 1.5 percentage points higher.

The cash you save by not paying a builder margin (typically 15 to 25 per cent of build cost) is real, but the financing cost and risk profile usually offset most of it. Owner-builder makes sense if you have direct trade experience, time, and a high tolerance for project risk. For most buyers, a fixed-price contract with a licensed builder is the cleaner path.

Conversion to a standard mortgage at handover

At practical completion the loan converts to a standard home loan automatically. The default product is variable-rate, principal-and-interest, with the rate at the time of conversion. You can typically negotiate at this point:

• A fixed-rate split (lock part or all of the loan at the current fixed rate)
• Interest-only structure if the property is investment
• An offset account or redraw facility, if not already configured
• A switch to a different lender (refinance), if your original lender\'s post-build pricing is uncompetitive

The conversion is a transition rather than a new application; the credit assessment, valuation, and security position are already in place. This is a good time to review competitive pricing because lender retention pricing on construction-loan conversions often does not reflect what new-borrower pricing would be.