The client
A household self-building in New Glasgow, Nova Scotia, with a signed builder contract and combined income of $7,500/month comfortably ahead of what the project needed. The contract itself, not the household's finances, is what stopped the file before it started.
Borrowers
Combined income $7,500/month
Both salaried, stable employment
Builder contract
Cost-plus (time-and-materials), no defined total
Estimated between $290,000 and $340,000
Renegotiated contract
$315,000 guaranteed-maximum-price
Inside the original cost-plus estimate's own range
Down payment
$15,750 — 5%, the minimum at this price
Price is under the $500,000 tier boundary
Other debt
$290/mo car loan
the only item on either bureau file
The problem
A cost-plus (time-and-materials) builder contract bills the actual cost of labour and materials as the project goes, with no fixed ceiling on the total. That is a perfectly ordinary way for a builder to price a custom self-build — it just isn't a number a construction-mortgage underwriter can lend against, because the as-complete appraisal, and the loan amount itself, need a fixed total to be measured against.
What the cost-plus contract actually said
- ▸Estimated project cost: $290,000 to $340,000 — a $50,000 spread, not a total
- ▸No guaranteed ceiling on what the household would actually owe the builder at completion
- ▸The lender's policy: no fixed price, no loan sizing — regardless of income or credit
The household's income and credit were never in question at any point in this file. What stalled it was entirely the shape of the contract itself — a $50,000 range where the lender needed one number, on a project that had otherwise passed every other check.
The numbers
Once the builder agreed to a fixed total, the file moved through underwriting on the numbers alone. The mortgage math itself never had to be reworked — it simply had nothing to attach to until the contract gave it something.
| The insured mortgage, sized to the fixed-price contract | Amount |
|---|---|
| Guaranteed-maximum-price contract total | $315,000 |
| Down payment (5%, the minimum at this price) | −$15,750 |
| Base mortgage | $299,250 |
| CMHC premium at 4.0% (90.01–95% LTV band) | +$11,970 |
| Total insured mortgage | $311,220 |
| Ratio check at the qualifying rate | Figure |
|---|---|
| Minimum qualifying rate on a 4.85% contract rate | 6.85% |
| Payment at the qualifying rate, 25 years | $2,151/mo |
| GDS (payment + $230 tax + $110 heat) ÷ $7,500 income | 33.2% |
| TDS (GDS numerator + $290 car loan) ÷ $7,500 income | 37.1% |
33.2% and 37.1% sit well inside CMHC's 39% and 44% maximums — the ratios were never close to a problem once the contract itself gave the lender something fixed to lend against. The $50,000 of contract uncertainty had been the entire obstacle, not the household's income.
The solution
A mortgage broker licensed under Nova Scotia's framework went back to the builder with the lender's specific objection in hand, rather than shopping for a lender willing to size a loan against an open-ended contract.
First, identified exactly what the lender's policy required. Not a lower price — a fixed one. A construction mortgage needs a defined total to size an as-complete appraisal against; an open-ended cost-plus contract gives it nothing to measure.
Second, brought that specific requirement back to the builder, not a general request to renegotiate. The builder converted the time-and-materials contract into a guaranteed-maximum-price contract capped at $315,000 — inside the original estimate's own $290,000–$340,000 range, so the household's expected cost barely moved.
Third, resubmitted the file with the fixed contract attached, changing nothing else. Same income, same down payment, same builder — only the contract's own structure had to change before the draw schedule could even be discussed.
The outcome
With a fixed total to lend against, the file cleared underwriting on the numbers alone: insured at 95% LTV, GDS 33.2%, TDS 37.1%. Nothing about the household's income or credit ever needed a second look.
The renegotiated $315,000 figure landed inside the original cost-plus estimate's own range, so the household's real construction cost was never materially different — only the contract's structure changed.
What to take from this file
- 01A construction-mortgage lender needs a fixed total, not just a realistic estimate. A cost-plus contract's own price range, however reasonable, isn't a number underwriting can size a loan against.
- 02Identify the lender's specific objection before going back to the builder. Asking for a fixed price, not a lower one, is a different and much easier conversation.
- 03A guaranteed-maximum-price rider can resolve this without abandoning the original builder relationship. The household never had to find a new contractor, only a new contract structure.
- 04Contract-type problems and income problems look identical from the outside until you separate them. This file's income and credit were fine throughout; only the paperwork's shape was ever in question.
- 05Fix the contract before touching anything else in the file. Once the total was defined, the ratios, the down payment and the premium band all followed exactly as they would on any ordinary insured build.
Sources
Every regulatory figure in this file traces to one of these primary sources. Client details and anything that varies by lender are illustrative, as flagged below.
- ▸CMHC — Purchase (Mortgage Loan Insurance) — default-insurance premium schedule by LTV band (25-year amortization).
- ▸CMHC — CMHC Home Start — minimum down payment tiers (5%/10%) and the $1.5M insured price cap.
- ▸OSFI — Minimum qualifying rate for uninsured mortgages — the minimum qualifying rate — greater of contract rate + 2% or 5.25%.
- ▸CMHC — CMHC Reviews Underwriting Criteria — GDS 39% / TDS 44% maximums and the 600 credit-score floor for insured files.
- ▸Provincial/territorial mortgage-broker legislation fetched directly (bclaws.gov.bc.ca, legisquebec.gouv.qc.ca, fcaa.gov.sk.ca, web2.gov.mb.ca, nslegislature.ca, assembly.nl.ca) plus FCNB's own site for NB and CanLII's index for PE — see notes for per-province method — provincial mortgage regulators and licence titles.
Illustrative in this file — lender-specific, not rules:
- ▸4.85% contract rate — rates move daily; not a quote.
- ▸the cost-plus estimate range and the guaranteed-maximum-price figure — builder contract terms and pricing are negotiated per project, not published.
Authority & provenance
How this case file was built
We publish the origin, the verification method and the reviewer for every case file, so you can judge how far to trust it before you rely on it with a client.
Where it comes from
Derived from files handled by Treadstone’s fulfillment desk and from scenarios contributed by partner brokerages. Names, employers, exact amounts and dates are changed so no client or file is identifiable.
Provenance: Composite — a pattern seen repeatedly on fulfilled files, not a single transaction.
What is verified
Every regulatory figure traces to a primary source listed above and was checked against it on the date shown. The arithmetic is recomputed by machine on every rebuild.
Anything that varies by lender is labelled illustrative rather than stated as a rule.
Who reviewed it
Reviewed for Canadian regulatory accuracy before publication, and re-checked whenever a cited rule changes.
Reviewed by: Nicholas Parson, Treadstone Associates — reviews every case file before publication.
This case file is professional reference material for licensed mortgage professionals. It is not advice to a borrower, and it is not a lender commitment. Insurer rules, qualifying rates and provincial taxes change — confirm the current position with the insurer, regulator or lender before you rely on any figure here in a live file.