What Capitalised Interest Does to Your Development Loan
Interest on a development facility is drawn against the loan, not paid monthly. See what the interest reserve does to your build headroom before you sign.
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Capitalised Interest / Interest Reserve / Loan to Cost
On most development facilities interest is not paid monthly out of your pocket. It is drawn against the loan and added to the balance, which means the facility you sign is not the balance you repay.
Quick Answer
On a development facility, interest is usually not paid monthly from your own cash. It is drawn against the loan and added to the balance, which makes capitalised interest a cost line inside your total development cost rather than a cashflow item.
Is Interest Paid or Drawn on a Development Loan?
Interest on a development loan is drawn, not paid. The lender charges it each month exactly as it would on any other facility, then debits the charge to the loan account instead of collecting it from your bank account.
Nothing leaves your account during the build. That is the reframe most first-time developers miss, because every other loan they have held behaved the opposite way, with a direct debit landing on the same date each month and a balance that fell rather than climbed.
The consequence is not that interest disappears. It moves out of your cashflow and into your capitalised interest balance, and from there into the total you have to clear when the completed stock settles or the facility is refinanced. A facility built this way is designed around a project that produces no income until it sells, which is exactly what a development is.
So the question stops being whether you can afford the repayments and becomes whether the end value clears the balance the facility will have grown into by completion. That is a different test with a different answer, and it is the one development finance is actually built around. It is also why a project with no serviceability problem at all can still fail on structure.
Once you accept that framing, the interest line stops looking like a cost you pay and starts looking like a slice of your approved limit that has already been spoken for before the first slab is poured.
Why Is the Loan You Sign Not the Loan You Repay?
The loan you sign is not the loan you repay because the interest line sits inside the same limit as everything else, and it grows while the rest of the budget is being spent. Your approved limit is a ceiling made up of several cost categories, and interest is one of them.
The table below sets out how the main cost lines on a development typically split between your own cash and the facility. The mix moves with structure and with the funder, so read it as the shape rather than the rule.
| Cost line | Usually funded from your cash | Usually drawn against the facility |
|---|---|---|
| Site acquisition | Deposit and equity contribution | Part funded at settlement |
| Construction progress claims | Rarely | Released through staged drawdowns |
| Interest during the build | Usually not | Capitalised to the balance |
| Establishment and line fees | Sometimes | Commonly capitalised at settlement |
| Quantity surveyor and valuation fees | Often paid upfront | Can be added to the facility |
| Authority contributions and headworks | Often cash | Can sit inside total cost |
| Contingency | No | Held undrawn until a variation is approved |
| Sales and marketing | Sometimes | Often inside total cost |
Read that as a single pool rather than eight separate ones. Every line drawn against the facility competes with every other line for the same ceiling, which is why the interest reserve is a cost item in its own right and not an afterthought bolted on at the end.
Where this commonly lands is a developer who has budgeted construction to the dollar off a quantity surveyor report, then finds the interest set-aside has quietly taken a slice of what they thought was build money.
What Sits Inside Total Development Cost?
Total development cost is the all-in number a lender sizes the facility against, and it includes the interest you will not be paying. Land, hard construction, professional fees, authority contributions, contingency, selling costs and the interest reserve all sit in the same stack.
That matters because the funding ratio is struck against that stack, not against the build contract on its own. A borrower who thinks of the facility as construction funding with some fees attached has the relationship backwards. The facility is a percentage of a total, and construction is only one line in the total.
The second half of the assessment runs against value rather than cost. The completed project is tested at gross realisation value, and the facility has to clear comfortably underneath it once interest has accrued. Cost sets what you can draw and value sets whether the drawn balance can be repaid, and both tests have to pass at the same time.
Where a project is short against the cost test rather than the value test, the gap is usually filled with equity, mezzanine finance or a reworked scope. What the equity tiers actually unlock is covered in our note on development finance equity tiers, and the funding that carries a site before the build loan begins sits in funding a development before the build loan starts.
How Does the Interest Reserve Cut Your Build Headroom?
The interest reserve cuts your build headroom because it consumes limit that would otherwise fund construction. A lender sets a maximum loan to cost ratio against the whole project, and interest sits inside that cost stack alongside land, build and professional fees. Push the interest line up and something else comes down, or your equity contribution goes up.
The reserve is a set-aside sized to the expected build term, indicative and varies by lender. It is calculated on an assumed drawdown profile rather than on your full limit from day one, because staged drawdowns mean the balance climbs gradually across the program.
That has a counterintuitive effect. A slower early program can reduce the interest bill even while it stretches the calendar, and a fast build that draws heavily up front can cost more interest than the term alone suggests. Term and profile move the number in different directions, and only one of them is visible on a Gantt chart.
| Input | Effect on the reserve | How much you control |
|---|---|---|
| Assumed build term | Longer term, larger reserve | High, through the program you submit |
| Drawdown profile | Front-loaded draws, larger reserve | Moderate, through the claim schedule |
| Interest rate | Higher rate, larger reserve | Low, it moves with the market |
| Authority and approval lead times | Delays extend the term, larger reserve | Moderate, through early lodgement |
| Sell-down start date | Later settlements, longer facility | Moderate, through the sales strategy |
| Contingency drawn early | No direct effect, but the buffer is gone | High |
| The lender's own assumptions | Conservative assumptions, larger reserve | Low, but testable before you sign |
Rate levels matter here in a way they do not on a fixed-fee cost line, because the reserve is the one budget item that moves with the cash rate. The current target rate and the schedule of upcoming decisions are published by the Reserve Bank of Australia, and a reserve struck under one rate environment does not automatically hold under another.
What Does a Month of Delay Actually Cost You?
A month of delay costs you a month of capitalised interest against a balance sitting at or near its peak, and that is the cost most feasibilities understate. A wet season, a late authority approval or a trade sequencing problem does not just move your settlement date.
It extends the period over which the facility charges interest at the worst possible point in the curve, because the heaviest drawdown months are the last ones. Interest on an almost fully drawn facility is a materially different number from interest in month 2, even though both are described as one month of delay in the site meeting.
Put approximate numbers on it. On a facility of around $3 million where the balance across the overrun averages roughly $2 million, an indicative rate of about 9 per cent puts the carry near $15,000 a month, so a 3 month slip costs in the order of $45,000. Those figures are illustrative only and move with the rate, the drawn balance and the term.
That $45,000 was going to pay a builder. It now pays interest instead, and nothing on the cost side of the feasibility changed to cause it.
The practical implication is that program risk and funding risk are the same risk on a development facility. A builder who protects the critical path is protecting the loan balance, whether or not anyone frames it that way. That is one reason the builder is underwritten as closely as you are, as set out in the builder your lender has to approve too.
How Is the Interest Reserve Sized?
The interest reserve is sized by modelling the expected balance month by month across the assumed term and applying the facility rate to it. It is arithmetic, not judgement, but every input into the arithmetic is a judgement someone has made.
The assumed term usually comes from your program, sometimes with a margin added. The assumed drawdown profile comes from the claim schedule in the building contract, cross-checked against the cost report. The rate comes from the letter of offer. Change any one of the three and the reserve moves, which is why two offers on the same feasibility can leave you with very different build money.
Major banks, non-bank lenders and specialist funders each apply different margins to those assumptions. A funder that adds 3 months to every program as a matter of policy is not being unreasonable, but it is quietly taking 3 months of interest out of your construction budget, and you will not see that on the rate sheet.
The reserve also has to survive the tail. If the facility term runs past practical completion to allow for a sell-down, the reserve normally has to cover that period too, since the balance stays outstanding until contracts settle. How that assumed period gets tested is the subject of how a lender tests your sell-down assumption, and it is the input developers most often leave at best case.
How Do You Test the Interest Line Before You Sign?
You test the interest line by interrogating the assumptions the reserve was built on rather than by negotiating the rate. The rate is usually the least movable of the three inputs, and the other two are yours to influence.
- Ask what build term the reserve was sized to. Not what term you submitted, what term the funder actually used. The difference between the two is a real number and it belongs to you.
- Ask for the assumed drawdown profile. A reserve modelled on a straight-line draw will understate a front-loaded build and overstate a slow start.
- Rerun your feasibility with a longer term. If the project only works on the base case program, it is a program-risk project, not a cost-risk project.
- Confirm whether the reserve covers the sell-down period. A reserve that stops at practical completion leaves the tail unfunded.
- Keep contingency separate from the reserve. The moment contingency is doing double duty as an interest buffer, you have one buffer, not two.
- Align the claim schedule with the drawdown calendar. Claims that arrive out of sequence with drawdowns create short-term funding gaps the reserve was never sized for.
- Get the paperwork in early. A shorter assumed term is a smaller reserve, and the construction loan pack is what shortens it.
None of that requires a different lender. It requires the questions to be asked before the letter of offer is signed rather than after the second progress claim, when the answers stop being negotiable.
What Happens if the Reserve Runs Out Mid Build?
If the reserve runs out mid build, the shortfall has to be funded from somewhere else in the stack, and the options narrow the later it is raised. There is no version of this where the interest simply stops accruing.
| Source | How it reads to a lender | When it is realistically available |
|---|---|---|
| Unspent contingency | Cleanest, it was budgeted for exactly this | Any time, provided it has not been spent |
| Fresh equity from the borrower | Straightforward where it can be evidenced | Depends on how fast you can produce it |
| A variation to the facility limit | A credit decision, not an administrative one | Slow, and slower after a declined drawdown |
| Deferred professional fees | Reads as cashflow stress on the project | Only where consultants agree in writing |
| A second position facility | Adds cost and needs the senior lender's consent | Late, and priced accordingly |
| Early release of sale proceeds | Only where contracts have actually settled | Tied to your sell-down, not your program |
Raise it before the reserve is exhausted. A request made early reads as project management, and the same request made after a drawdown has been declined reads as distress, even where the underlying numbers are identical.
One point worth flagging: a variation to the limit is an amendment to a credit contract, and the terms attaching to it, including any change to security or guarantees, are a legal question for your solicitor rather than something a broker should be interpreting for you. Get the deed read before you sign the variation, not after. A director guarantee given behind a development facility also follows you onto your own file, which is set out in how a business guarantee reads on a One Doc home loan.
If the project is otherwise sound and the gap is genuinely a timing problem, the funders who read that situation most comfortably are usually outside the majors. Where their appetite currently sits is covered in the non-bank development funding market read.
Capitalised interest is not a rate question, it is a capacity question. Because interest is drawn against the facility rather than paid from your cash, it sits inside total development cost and competes with land, build and contingency for the same limit. A longer assumed program, a front-loaded drawdown profile or an untested sell-down period can therefore reduce the amount of actual construction your development finance facility will fund, without a single build cost changing.
Key takeaway: Test the assumed build term and drawdown profile behind the interest reserve before you sign, because those two assumptions set your real construction headroom.Frequently Asked Questions
The difference is who pays it and when. Ordinary interest is charged and settled from your own cash each month, while capitalised interest is drawn against the facility and added to the outstanding balance, so nothing leaves your account during the build. The cost is identical in substance, but capitalised interest compounds against a rising balance and is carried by the lender until the project is sold or refinanced.
You usually make no repayments out of pocket during construction, because interest is drawn rather than paid for the duration of the build. The interest accrues against the drawn balance and is settled when the facility is repaid from sale proceeds or a refinance. Some facilities require monthly servicing on the land component only, so read the letter of offer rather than assuming, and check how staged drawdowns are scheduled before you sign.
Capitalised interest counts towards the loan to cost ratio on most development facilities, because the interest reserve is a line item in total development cost rather than a separate charge sitting outside it. That means the interest line competes with land, construction, professional fees and contingency for the same limit, which is why a longer assumed build term can reduce the amount of construction you are actually able to fund.
Some funders will allow monthly servicing of part or all of the interest, most often on the land component, and it can free up limit for construction where you have the cashflow to support it. It is a structural question rather than a preference, because the funder still has to be satisfied the payments can be met from income that does not depend on the project selling. Raise it before the offer is issued, alongside the equity position covered in our note on development finance equity tiers.
The accrued balance does not shrink because the sale price did. Sale proceeds discharge the facility first, and any shortfall between the balance and the net proceeds falls back on the borrower and on whoever gave security or a guarantee for it. That is why the assumed sale prices behind the feasibility get tested so hard, a process set out in how a lender tests your sell-down assumption.
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