How Construction Loans Work

Building a new home involves a different lending process to buying an existing property, and I find a lot of clients are surprised by how much more involved it is. Here is how construction lending actually works, from land through to the finished build.

What a construction loan actually is

Rather than releasing the full loan amount in one lump sum at settlement, a construction loan releases funds in stages as the build progresses, matched against completed work. You typically only pay interest on the portion of the loan that has actually been drawn down at any point, rather than the full approved amount from day one, which can make the early stages of a build noticeably cheaper than the finished loan will eventually be.

How staged funding works

Construction loans release funds at agreed stages, commonly aligned with milestones such as foundation completion, framing, enclosing the building, and final fit out, though the exact stages depend on your builder's contract and your lender's own requirements. Before each payment is released, the lender typically arranges an inspection or a registered valuer's report confirming the work claimed has actually been completed to that stage.

This staged approach protects both you and the lender, since funds are only released against verified progress rather than a builder's own invoice alone. It also means the timing of your payments is tied to actual construction progress, not a calendar schedule, so delays in the build itself will naturally shift when each stage payment is due.

Interest costs during construction

Since you only pay interest on funds actually drawn down, your repayments early in a build are lower than they will be once the loan is fully drawn at completion. This is genuinely useful, but it also means your repayments will step up over the course of the build as more of the loan is released, which is worth planning for rather than being surprised by. I generally walk clients through what their repayments will look like at each stage, not just the final figure, so there are no surprises partway through.

Land purchase versus house and land package

If you are buying bare land and building separately, the land purchase itself is usually settled first, often on standard lending terms, with the construction loan then structured against the build once you have a signed building contract. A house and land package, where the land and build are purchased together as one arrangement, is sometimes structured slightly differently, and it is worth understanding which situation you are in before assuming the process will look identical to a standard purchase.

What lenders need before approving

Beyond the usual income and deposit assessment, lenders generally want a fixed price building contract from a registered builder, council consented plans, and evidence of the total build cost matching what is being borrowed. Some lenders also require a quantity surveyor's report to independently verify the build cost and staged payment schedule before approving the loan.

The role of your building contract

A fixed price contract matters more than people expect, since it protects you from cost overruns being passed on unexpectedly partway through the build. Lenders view a fixed price contract from a reputable, registered builder far more favourably than an estimate or a contract with significant variable pricing, since it reduces the risk of the project running over budget in a way that could affect your ability to complete it.

It is also worth understanding what is and is not included in your contract price. Site works, landscaping, driveways, and connections to services are sometimes priced separately from the main build, which can catch buyers off guard if they assumed everything was bundled into the one figure.

Code compliance and final release of funds

Once the build is complete, a Code Compliance Certificate is issued by the council confirming the work meets building code requirements. This is typically required before the final portion of your loan is released and before you can move in. It is worth building the time this takes into your expectations, since it does not happen the moment the last nail is in, and council processing times can add real weeks to your overall timeline beyond the physical construction itself.

Common mistakes with construction lending

• Underestimating total costs. Site works, landscaping, driveways and fencing are sometimes left out of an initial budget, only to surface as additional costs later.
• Not accounting for interest during the build. Interest on drawn funds during construction is a real, ongoing cost that should be budgeted for, not an afterthought.
• Choosing a builder without a genuinely fixed price contract. This shifts real financial risk onto you if costs rise during the build.
• Assuming the process moves at the same pace as buying an existing home. Construction lending has more steps and more parties involved, so it naturally takes longer to arrange.

Frequently asked questions