The client
A buyer purchasing an owner-occupied home in Moose Jaw, Saskatchewan, with a basement suite the seller had rented for years without ever obtaining a permit — no fire-separation inspection, no legal secondary-suite certificate, just a tenant paying $1,100 a month. The lease itself was solid. The suite's legal status was not.
Purchase
$268,000, Moose Jaw
5% down, the minimum at this price
Basement suite
Rents for $1,100/month
Never permitted or inspected by the seller
Buyer's income
$5,300/month T4
Not enough alone at this price
Other debt
$300/mo car loan
Unchanged by the purchase
Housing costs
Tax $260/mo; heat estimate $120/mo
Unaffected by the suite's status
The problem
Most rental-income policy questions are about WHAT PERCENTAGE of the rent a lender will add back to income. This file never got that far. The first lender's policy was explicit: no legal-suite documentation, no rent counted at all — not 50%, not 25%, zero.
A gate, not a discount
- ▸No permit, no fire-separation inspection, no municipal compliance letter on file
- ▸The lender's policy: an undocumented suite contributes $0 to income, regardless of lease strength
- ▸Without the suite's rent, GDS reaches 41.4% and TDS 47.1% — both over CMHC's maximums
The mortgage itself, at 95% LTV, was never the obstacle — the qualifying payment is identical whether the suite counts or not. The suite's legal status was the entire gate, and no amount of shopping for a lender with a more generous add-back percentage would have opened it.
The numbers
Structuring the loan showed exactly how much the suite's rent was worth once it counted at all — and confirmed the legal status, not the rent amount, was the single point of failure.
| The insured purchase | Amount |
|---|---|
| Purchase price | $268,000 |
| Down payment (5%, the minimum at this price) | −$13,400 |
| Base mortgage | $254,600 |
| CMHC premium at 4.0% (90.01–95% LTV band) | +$10,184 |
| Total insured mortgage | $264,784 |
| Ratio check | Suite excluded (unregistered) | Suite counted (legalized, 50% add-back) |
|---|---|---|
| Qualifying payment, 25 years | $1,814 | $1,814 |
| Income used | $5,300 | $5,850 ($5,300 + $550 add-back) |
| GDS (payment + $260 tax + $120 heat) ÷ income | 41.4% | 37.5% |
| TDS (GDS numerator + $300 car loan) ÷ income | 47.1% ✗ | 42.6% ✓ |
Both GDS and TDS moved by exactly the same margin once the suite counted, because the mortgage itself never changed — only the income side of each ratio did.
The mortgage itself — $264,784 at a 4.00% premium band — never changed. Every point of improvement came from the suite's rent becoming eligible to count at all, not from a bigger add-back percentage or a different loan structure.
The solution
An FCAA-licensed Saskatchewan mortgage broker treated the suite's legal status as a closing condition to fix, not a lender policy to shop around.
First, confirmed exactly what Moose Jaw's building and fire codes require for a legal secondary suite. The list was short and achievable: self-contained means of egress, smoke and CO alarms, and confirmed fire separation between units.
Second, made the retrofit a condition of the purchase agreement. The seller, who had been collecting the rent for years without ever legalizing it, completed the work and obtained a municipal compliance letter before closing.
Third, resubmitted the file with the compliance letter in hand, rather than switching to a lender with a laxer suite-documentation policy that might have created the same problem again at renewal or refinance.
The outcome
With the suite legalized before closing, a 50% add-back of its $1,100/month rent brought GDS to 37.5% and TDS to 42.6%, both inside CMHC's maximums. The purchase funded insured at 95% LTV exactly as first submitted, once the one real obstacle was cleared.
Bringing the suite into compliance also protects the buyer going forward — an undocumented suite can resurface as the same zero-credit problem at the next refinance or renewal, with a different lender running the same check.
What to take from this file
- 01An unregistered suite is a gate, not a discount. Some lenders count a documented suite's rent at a reduced percentage; an undocumented one, many will count at zero.
- 02Fix the legal status, don't just shop for a softer policy. A more permissive lender today doesn't protect the file at the next renewal or refinance.
- 03The retrofit list for a legal suite is often short and specific. Egress, smoke/CO alarms, and fire separation are the usual minimum — confirm the exact local requirements before assuming it's a bigger job than it is.
- 04Make legalization a condition of the purchase agreement, not a post-closing hope. The seller, who benefited from the rent for years, is the party with the most reason to complete it before the deal closes.
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:
- ▸4.75% contract rate — rates move daily; not a quote.
- ▸50% suite-income add-back — each lender sets its own add-back policy for a legal secondary suite once documented.
- ▸Saskatchewan closing costs — ISC's current land-titles fee schedule could not be independently verified, so no dollar figure is given here.
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.