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Construction Loans and Progress Payments

🏗️ How a Construction Loan Works

Financing a new build is different from buying an existing home. A construction loan does not hand over all the money at once; it releases funds in stages as the build progresses, called progress payments or drawdowns. You usually pay interest only on what has been drawn so far, and the loan converts to a normal mortgage once the home is finished.

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Key Point: A construction loan is drawn down in stages that match the build, such as foundations, frame, roof, and completion. Each drawdown is released after the bank confirms that stage is done. You pay interest only on the amount drawn so far, so payments start small and grow as the build progresses. When the home is complete, the loan typically becomes a standard mortgage. The contract type, fixed-price or cost-plus, strongly affects your risk of cost overruns.

Staged Drawdowns

Typical StageWhen Funds Release
FoundationsAfter the slab or foundations are done
Frame and roofOnce the structure is up and closed in
Fit-outAs interior work progresses
CompletionOn practical completion and code compliance

Why It Is Staged

The bank releases money only as value is added to the property, which protects them and you. It also means you are not paying interest on the whole loan from day one, since you only owe interest on what has actually been drawn.

💵 Interest and Payments During the Build

Interest Only on What Is Drawn

During construction you generally pay interest only, and only on the amount drawn so far. Early on, with just the foundations paid, the interest is small. As more is drawn for the frame, roof, and fit-out, the interest grows.

After the first drawdown, interest is charged on that amount only
Each further stage adds to the drawn balance and the interest
Payments rise through the build as more is drawn
On completion, the loan becomes a normal repayment mortgage

Budget for the Build Period

If you are renting while you build, you are paying rent plus the growing construction interest at the same time. Budgeting for this overlap is important, as it is a common pinch point that catches people out.

Two costs at once: While building, you may be paying both your current accommodation and rising construction loan interest. Plan for this double cost across the build, which can take many months.

Each Drawdown Needs Approval

The bank usually requires confirmation, such as an inspection or builder's certification, before releasing each stage. Delays in the build can delay drawdowns and payments to the builder, so keep the process moving and the paperwork ready.

📑 Fixed-Price vs Cost-Plus Contracts

The Contract Type Drives Your Risk

How your build contract is structured has a big effect on cost certainty.

ContractHow It WorksCost Risk
Fixed-priceAn agreed total for the defined workLower, but watch for excluded items and variations
Cost-plusYou pay the actual costs plus a marginHigher, the final cost is uncertain

Fixed-Price

A fixed-price contract gives a known total for the specified build, which suits financing because the bank and you know the number. But read what is included and excluded, and understand that variations and provisional sums can still change the price.

Cost-Plus

With cost-plus, you pay the real costs plus the builder's margin. It can suit complex or uncertain builds, but the final figure is open-ended, which is riskier for budgeting and finance. A contingency buffer is essential.

Always hold a contingency: Builds overrun more often than not, through variations, delays, and surprises. A contingency buffer on top of the contract price protects you from being caught short before completion.

💡 Common Mistakes

Mistake 1: Forgetting the Rent-Plus-Interest Overlap

Paying rent and rising construction interest together can strain a budget. Plan for both across the whole build.

Mistake 2: No Contingency

Assuming the contract price is the final cost is risky. Variations and overruns are common, so hold a buffer.

Mistake 3: Not Understanding the Contract

Fixed-price and cost-plus carry very different cost risk. Know which you have and what is included before signing.

Mistake 4: Expecting Money Up Front

Funds release in stages, after each is confirmed. Builders need to be paid in line with that, so understand the drawdown schedule.

A Simple Approach

1. Understand the staged drawdown schedule
2. Expect interest-only payments that grow through the build
3. Budget for rent plus construction interest together
4. Know whether your contract is fixed-price or cost-plus
5. Hold a contingency for overruns and variations

See our Building a House guide for the wider build process, and the Property New Build Calculator. Final word: a construction loan releases money in stages as the build progresses, with interest charged only on what is drawn, then converts to a normal mortgage. Plan for the build-period costs, understand your contract type, and hold a contingency. This is general information, not advice; work with your bank, lawyer, and builder.

🎯 Test Your Knowledge

Quiz on Construction Loans (20 Questions)

1. How does a construction loan release money?
All at once up front
Only at the end
In stages as the build progresses
Never
2. What are a construction loan's staged fund releases called?
Refunds
Dividends
Bonuses
Progress payments or drawdowns
3. What do you usually pay during the build?
Interest only on what has been drawn
Full principal and interest from day one
Nothing
Double interest
4. What is the interest like early in the build?
At its highest
Small, because little has been drawn
Zero forever
Fixed for the whole loan
5. What happens to payments as the build progresses?
Fall
Rise as more is drawn
Stay the same
Stop
6. When the home is complete, what does the loan typically do?
Is cancelled
Stays interest-only forever
Becomes a normal repayment mortgage
Is refunded
7. When is each drawdown released?
You ask once
The build finishes entirely
The bank confirms that stage is done
A year passes
8. Who does staging the loan protect?
Only the builder
Both the bank and you, releasing money as value is added
No one
Only the council
9. What might you pay while building and renting at the same time?
Nothing at all
Rent plus rising construction interest together
Only rent
A single fixed fee
10. What does a fixed-price contract give you?
An open-ended cost
An agreed total for the defined work
No price at all
A guaranteed refund
11. Under a cost-plus contract, what do you pay?
A fixed total only
Nothing
The actual costs plus a margin
Less than the costs
12. Which type of contract carries higher cost risk?
Cost-plus, since the final cost is uncertain
Fixed-price always
Neither
Renting
13. Why can even fixed-price contracts still change?
Nothing ever
The weather only
Your tax code
Variations and provisional sums
14. How important is a contingency buffer when building?
A waste of money
Never needed
Essential, since builds often overrun
Illegal
15. What can build delays cause?
Speed up funding
Lower your interest
Have no effect
Delay drawdowns and payments to the builder
16. What do you pay interest on during a construction loan?
The amount drawn so far, not the whole loan
The full loan from day one
Nothing
Double the drawn amount
17. What should you do before signing a build contract?
Know which type it is and what is included
Sign without reading
Ignore the inclusions
Assume nothing changes
18. What does a drawdown often need before release?
An inspection or builder's certification
Nothing
A new loan each time
A council sale
19. How long can the double cost during a build last?
A day
An hour
No time at all
Many months
20. What is the overall message about construction loan progress payments?
All money arrives up front
Contracts do not matter
No buffer is needed
Funds come in stages with growing interest; budget for it, know the contract, and hold a contingency

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