How Pre-Construction Mortgages Work

Why pre-construction financing is different

When you buy a resale home, you typically get a mortgage commitment within days of signing the offer and close within 30–90 days. The property is there to appraise; the lender can assess its current market value; and your financial situation today determines your qualification.

Pre-construction is different in every dimension. You are purchasing something that will not be built for two to five years. There is no property to appraise at signing — the appraisal happens closer to closing. Your financial situation and the rules governing mortgage qualification may change significantly between when you sign and when you close. Interest rates will almost certainly be different. The market value of the unit at closing may be higher or lower than what you paid.

A mortgage commitment you receive today is not useful for a closing that is three years away — lenders will not commit to a rate or even an approval for that duration. This means that most pre-construction buyers go through the mortgage process twice: a preliminary assessment at the time of signing to confirm they are in the general range of qualification, and a full mortgage commitment arranged 90–120 days before the confirmed closing date.

Rate holds: what they are and how they work

A rate hold (also called a rate commitment) is a lender's guarantee that a specific interest rate will be available to you for a defined period, regardless of whether rates rise in the interim. Rate holds are typically available for 90 to 130 days. Some lenders offer longer holds — up to 120 days is common; some offer up to 180 days for premium products.

For pre-construction buyers, a rate hold becomes relevant only when the closing date is firm and within the hold period. You cannot meaningfully lock in a rate three years before closing — most rate holds are completely unreachable on that timeline. Even if a lender offers a "pre-construction rate hold," read the fine print carefully: these are typically promotional products with conversion fees or conditions attached.

What actually happens: as your confirmed closing date approaches, your mortgage broker will begin shopping for the best rate and product approximately 90–120 days out, obtaining a rate hold at that time. If rates drop before closing, some lenders allow you to take the lower rate instead — this varies by product and institution.

If your builder extends your closing date beyond the expiry of your rate hold, you will need to obtain a new hold at whatever rates prevail at that time. This is one of the real financial consequences of delays — not just the inconvenience, but the potential loss of a favourable rate hold.

Pre-approval vs. mortgage approval for pre-construction

A pre-approval at signing is a preliminary assessment based on your current income, debts, credit history, and the purchase price. It tells you whether you are in a reasonable range to qualify — but it is not a binding commitment and it is subject to the lender's policies and rates at the time of your actual closing.

Getting a pre-approval before signing is still valuable. It confirms you are not committing to a purchase price that is well beyond your means, and it gives your lawyer and financial advisor a baseline for planning. However, you should treat it as a starting point, not a guarantee.

The actual mortgage approval — with confirmed rate, terms, and underwriting — happens closer to closing. At that point, the lender will require a full income verification package (pay stubs, T4s, NOA, employment letter), a property appraisal, and current qualification under the rules in effect at that time. If the stress test rate has changed, your qualifying income requirements will be different from what was assessed at signing.

How lenders assess pre-construction purchases

Lenders evaluate pre-construction mortgage applications with specific considerations that differ from resale:

• Income and debt service: Your Gross Debt Service (GDS) and Total Debt Service (TDS) ratios are calculated the same way as resale — but based on your income at the time of the actual mortgage application, which may be different from signing day.
• Existing mortgage obligations: If you own another property and still carry a mortgage at closing time, that payment is factored into your TDS ratio, potentially reducing how much you can borrow.
• The stress test: As of 2024–2026, the qualifying rate under Canada's mortgage stress test is the greater of the contract rate plus 2%, or 5.25%. If rates rise significantly before closing, the stress test threshold rises with them, making qualification harder.
• Loan-to-value on current appraised value: The lender will appraise the property at current market value at closing — not at your purchase price from three years ago. If the appraised value is lower than your purchase price, the lender bases the loan on the appraised value, and you must cover the gap in cash.

What happens if market values drop before closing

This is one of the most significant risks in pre-construction financing that many buyers underestimate at signing. If the real estate market declines between when you sign and when you close, the appraised value of your unit at closing may be less than the purchase price you agreed to pay.

In this scenario, the lender will only provide a mortgage based on the appraised value — not the purchase price. You are still legally obligated to pay the full purchase price (the APS is binding). The difference must be made up in cash at closing. If a $750,000 unit appraises at $680,000, you need an additional $70,000 in cash on closing day — on top of your closing costs.

This scenario is not theoretical. It occurred for many buyers in 2023 who had purchased in 2020–2021 at peak prices. Buyers who had budgeted tightly for their deposits and closing costs found themselves short at closing, sometimes forced to attempt an assignment sale or, in the worst cases, failing to close and losing their deposits.

The lesson: buyers who purchase pre-construction should have a financial cushion beyond their planned down payment — specifically to manage the risk of an appraisal shortfall at closing.

CMHC and Sagen mortgage insurance for new construction

If your down payment is less than 20% of the purchase price, your mortgage must be insured by CMHC, Sagen (formerly Genworth), or Canada Guaranty. Mortgage insurance premiums range from 0.60% to 4.00% of the mortgage amount, depending on your loan-to-value ratio, and are added to your mortgage balance at closing.

For pre-construction, insured mortgages have a specific rule called the cap test that applies at closing.

The cap test: the insured mortgage rule that catches buyers off guard

For an insured mortgage (less than 20% down payment), the purchase price must not exceed the property's current appraised value at closing. This is the cap test. If the unit appraised at $600,000 but you agreed to pay $650,000 three years ago, your insured mortgage is capped at what the lender will advance on a $600,000 value — even though you owe $650,000. You must cover the $50,000 gap in cash.

Additionally, for insured mortgages, the purchase price is subject to the maximum insured property value limit (currently $1,500,000 as of 2024, following the federal increase from $999,999). Properties above this threshold are not eligible for insured financing and require at least 20% down.

Buyers who plan to purchase pre-construction with less than 20% down need to think carefully about appraisal risk. If market values decline between signing and closing, the combination of the appraisal shortfall and the cap test can create a significant cash gap at closing. A mortgage broker who specializes in pre-construction can model this scenario specifically for your purchase price and timeline.

Working with a mortgage broker who specializes in pre-construction

A mortgage broker who handles pre-construction regularly understands the timing issues, the appraisal risks, the lender policies specific to new construction, and how to structure a strategy from signing day through to closing. This is meaningfully different from a broker who primarily handles resale transactions.

Ask a prospective broker: How many pre-construction closings have you handled? Which lenders do you work with for new construction? Have you had clients face appraisal shortfalls, and how did you handle them? A specialist will have clear answers to all of these.

Your broker should also be able to advise on how to structure your deposit payments in relation to your mortgage strategy — particularly whether to keep funds in a FHSA or RRSP for the Home Buyers' Plan versus maintaining liquidity, and how to plan for the closing costs that will be due simultaneously with your mortgage activation.