ChatGPT · National
We're partway through building our home and costs have gone up. What should we talk through with the lender before the extra costs become a problem?
It’s good to talk to the lender before you’re forced into a last-minute decision. In New Zealand, construction lending is usually released in stages, so a cost increase can affect not just the final loan amount but also whether there is enough money available to complete the next stages. ANZ Bank
Here are the main things to work through with your lender:
1. How much of the extra cost can your current loan cover?
Ask:
- “What is our remaining approved construction budget?”
- “Do we have any contingency allowance left?”
- “If the build costs increase by $X, can the current facility cover it?”
- “Would we need a new loan application or top-up?”
If you need more borrowing, the lender will generally look at your ability to service the extra debt and the value of the completed home. ANZ Bank
2. Whether the completed home value still supports the borrowing
Ask:
- “What is the latest estimated value of the finished property?”
- “Would the increased build cost create a shortfall between the loan and the property value?”
- “Would you require another valuation?”
A higher build cost does not automatically mean the bank will lend more; the lender will consider the end value and affordability. Westpac NZ
3. Which costs are genuine overruns versus optional changes
Go through the budget line by line:
- Builder variations
- Site works (earthworks, drainage, retaining, access)
- Materials price increases
- Upgrades you’ve chosen
- Items originally excluded from the contract
- Delays that may increase costs
Ask your lender what documentation they need for variations and whether they need updated quotes or approvals before releasing funds. Keeping records of invoices, variations and builder correspondence is important. ANZ Bank
4. Whether you should change the scope of the build
Before borrowing more, ask:
- “Which items could we defer until after completion?”
- “Are there parts of the build we can downgrade without affecting the lending approval?”
- “Would removing certain items help us stay within the approved facility?”
Sometimes finishing the essential parts of the home and postponing non-essential upgrades is the safer option.
5. What happens if the build takes longer
Ask:
- “What happens to our loan if the completion date moves?”
- “Will delays affect our interest costs or loan conditions?”
- “Do we need to update you now?”
During construction, interest costs can rise as more of the loan is drawn down. ANZ Bank
6. How repayments will look after completion
Ask for a realistic projection:
- New loan balance
- Expected repayments
- Interest rate options once the build is finished
- Whether the repayment level still fits your budget if rates change
Take these documents to the lender
It helps to have:
- Current builder cost-to-complete statement
- Original contract and all variations
- Updated budget
- Latest invoices
- Current loan balance and remaining drawdowns
- Any new quotes
A useful opening question for the lender is:
“Our build is tracking over budget and we want to make sure we have a plan before it affects completion. Can we review the remaining construction facility, expected final cost, and our options if we need more funding?”
If you share whether this is a new build, renovation, or house-and-land package, and whether the extra costs are from builder variations, unexpected site costs, or price increases, I can suggest more specific questions to take to the lender.
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Captured 11 October 2026