Simple hacks to fund a custom home build in WA

How Construction Finance Works for Custom Builds

Construction finance for a custom home covers both the land purchase and the building costs, releasing funds progressively as your project reaches specific milestones. Unlike a standard home loan where you receive the full amount upfront, lenders release funds in instalments based on progress inspections, which means you only pay interest on what's been drawn down at each stage.

Consider a buyer who has found suitable land in Byford and engaged a registered builder for a custom design. The total project sits at around the current median for a completed home in the area, with the land component representing roughly 30% of that total. The lender approves the full loan amount but releases the land portion at settlement, then disburses the remaining funds across five stages: base, frame, lock-up, fixing, and practical completion. At the base stage, the builder submits certification and the lender arranges a progress inspection before releasing that portion. Interest accrues only on the land cost and the base payment combined, not the full loan amount.

Most lenders structure these as a construction to permanent loan, which means the facility automatically converts to a standard home loan once building is complete. You'll typically make interest-only repayments during construction, then switch to principal and interest once you move in. The approval process requires council plans, a fixed price building contract, and evidence that building will commence within a set period from the disclosure date, usually six to twelve months depending on the lender.

What Lenders Look for in a Custom Home Application

Lenders assess both your borrowing capacity and the viability of the project itself. They want to see a fixed price contract with a registered builder, council approval for the design, and confirmation that the land is suitable for the proposed build. The contract needs to include a clear progress payment schedule that aligns with the lender's drawdown structure.

In our experience with clients across Greater Perth, one of the most common delays happens when the builder's payment schedule doesn't match the lender's standard stages. A builder might request payment at wall completion, but the lender only releases funds at lock-up, which occurs later. Resolving this before lodging the construction loan application saves weeks of back-and-forth. Your broker should review both documents side by side and flag any misalignment before formal submission.

Lenders also apply a margin to the contract price, typically holding back 10% to 15% as a buffer against cost overruns. If your builder quotes the project and the lender's valuer agrees with that figure, the lender might still only approve funding up to 85% of the contract value unless you can demonstrate additional savings or equity. This isn't about doubting the builder; it's a standard risk management approach for custom projects where variations can emerge during construction.

The Progressive Drawdown Process and Timing

Once construction begins, the builder will notify you when each stage is ready for inspection. You'll then request a drawdown from the lender, who arranges a progress inspection within a few business days. The inspector confirms the work matches the stage claimed, and the lender releases funds directly to the builder, usually within 48 hours of a satisfactory report.

Timing matters because builders often require payment before moving to the next stage. If there's a delay between stage completion and drawdown approval, it can hold up trades like plumbers or electricians who are scheduled for the following phase. Most lenders charge a progressive drawing fee each time funds are released, typically between $300 and $500 per drawdown depending on the institution. These fees are separate from the interest you're paying on drawn amounts, so factor them into your budget from the outset.

For buyers building in regional WA, some lenders limit the distance their inspectors will travel or charge additional fees for remote inspections. If you're building outside the Perth metro area, confirm inspection availability during the application stage rather than discovering limitations once construction is underway. We regularly see this affect timelines for clients in places like Mandurah, Bunbury, or further north.

Interest Costs During Construction

You only pay interest on the amount drawn down at any given time, not the full approved loan amount. If your total facility is approved and you've drawn down for land plus the first two stages of construction, your interest calculation is based on that combined figure alone.

As an example, a buyer building in Ellenbrook with a total loan approval might have drawn down for land and base stage, bringing the total to a specific sum by month three of construction. At current variable rates, monthly interest on that amount would sit in a particular range, far lower than if the full loan amount was active from day one. By the time the build reaches practical completion and all funds are drawn, the buyer has saved several thousand dollars in interest compared to a scenario where the full loan was drawn upfront.

Most lenders offer interest-only repayment options during the construction phase, which keeps your monthly commitment lower while you're potentially still paying rent or managing other housing costs. Once the build is complete and the loan converts to a standard facility, you'll switch to principal and interest repayments unless you negotiate an extended interest-only period, which is common for investment loans but less typical for owner-occupied builds.

Fixed Price Contracts vs Cost Plus Arrangements

Almost all lenders require a fixed price building contract for custom home finance. A cost plus contract, where you pay the builder's costs plus a margin, introduces too much uncertainty for the lender to assess risk accurately. If your builder only works on a cost plus basis, you'll struggle to secure construction funding from a major lender and may need to explore specialist providers or private funding.

The fixed price contract protects both you and the lender from unexpected cost blowouts, though it doesn't eliminate variations entirely. If you decide mid-build to upgrade benchtops or add a feature wall, the builder will issue a variation and you'll need to cover that cost separately, either from savings or by increasing the loan if you have available equity. The lender won't automatically approve additional funds for variations, so plan your finishes before signing the contract rather than expecting flexibility once construction starts.

For buyers considering a custom design in areas like Baldivis or Two Rocks, where estate guidelines can be strict, confirm that your design meets all covenant requirements before lodging the construction loan application. A lender won't proceed if the development application is likely to be rejected or delayed by the local council or estate management.

Land and Construction Packages vs Separate Purchases

Some buyers purchase land first, then arrange a building contract later. Others commit to a land and construction package where both elements are coordinated from the start. Lenders can accommodate either structure, but the approach affects timing and approval conditions.

If you already own the land outright or with existing equity, you can use that as part of your deposit for the construction component. The lender values the land, applies that figure to your equity position, and then assesses how much additional funding you need for the build. If you're buying land and building simultaneously, the lender treats it as a single transaction and releases the land portion at settlement, with construction funds following the usual progress payment schedule.

Buyers working with a land and build loan sometimes face longer settlement periods, especially if the land is part of a new estate where titles haven't been issued yet. You might sign a contract to purchase land that won't settle for six to nine months, during which time your finance approval could expire. Most lenders issue conditional approval valid for three to six months, so coordinate your land settlement and building commencement dates to avoid needing to reapply or extend approval, which can trigger additional credit checks and valuation fees.

How Owner Builder Finance Differs

If you're planning to manage the build yourself rather than hiring a registered builder, the lending landscape changes significantly. Most mainstream lenders won't offer owner builder finance due to the higher risk of cost overruns and construction delays. Specialist lenders exist, but they typically require a larger deposit, charge higher interest, and impose stricter progress payment conditions.

Owner builders need to demonstrate construction experience, provide detailed costings for every trade, and often accept lower loan-to-value ratios, sometimes capped at 60% to 70% of the total project value. Unless you have substantial savings or equity, owner builder finance may not be viable for a custom home project. For most buyers across WA, engaging a registered builder and accessing standard construction finance delivers lower costs and smoother approvals than attempting an owner builder approach.

Preparing Your Application

Before lodging your construction loan application, gather the fixed price building contract, council-approved plans, proof of land purchase or ownership, and evidence of your savings or deposit. Lenders want to see genuine savings held for at least three months, though they'll also accept equity from an existing property or a gifted deposit from family in some cases.

Your broker should review the builder's progress payment schedule alongside the lender's standard drawdown structure and confirm alignment before submission. If the builder requires payment at stages that don't match the lender's inspection points, negotiate adjustments with the builder early. Once the loan is approved and construction begins, changing the payment schedule becomes difficult and can delay funding at critical stages.

For buyers building a custom design, especially in growth areas like Alkimos or Lakelands, allow extra time for council approval compared to a standard project home. Custom designs often require additional documentation or amendments to meet local planning requirements, which can push out your commencement date and affect your finance approval timeframe. If your lender requires building to start within six months of the disclosure date and council delays add three months to your timeline, you may need to extend or reapply for finance.

Call one of our team or book an appointment at a time that works for you to discuss your custom home project and confirm which lenders align with your build timeline and budget.

Frequently Asked Questions