Short answer
Ontario says a building permit is required to add a second unit. A lender may still assess existing or proposed rent under its policy, but zoning, permits, fire and building compliance can affect the appraisal, insurability, marketability and amount of rent accepted.
The client problem behind the question
The listing calls the basement an apartment and includes rent in the marketing, but the seller cannot produce permits or municipal records.
What the official guidance establishes
Ontario directs owners adding a second unit to apply through the local building department. Municipal zoning, Ontario Building Code requirements and Residential Tenancies Act obligations can also apply.
Where the answer can change
A lender accepting some rent does not legalize the unit. “Existing,” “legal,” “authorized” and “retrofit” are not interchangeable. Appraisers and lenders may describe the same unit differently, and insurance coverage must be confirmed.
A practical Ontario example
Illustration only: A buyer needs $1,800 monthly basement rent to qualify. The appraisal identifies the unit but notes no permit record. One lender reduces or rejects the rent while another requests municipal confirmation and a market-rent schedule.
What to do before committing
Obtain municipal records, permits, inspection status, lease details, utility arrangement and an insurance quote before waiving conditions. Qualify once with the expected rent and once without it so the risk is visible.
Questions Rajiv would ask
- What deadline, condition or closing problem must be solved?
- Which facts are confirmed by original documents and which are still assumptions?
- Which law, insurer rule or lender policy applies to this exact transaction?
- What happens to the cash requirement and monthly payment if the first option fails?
- What is the practical route back to lower-cost financing, if temporary financing is used?
Rajiv’s broker perspective
I would match the financing to the contractor schedule, not only to the finished value. The practical review includes how much cash is needed before each draw, whether permits and rent are supportable, and what happens if the project costs more or takes longer. A, alternative/B, MIC and private options can each work, but the exit and total cost must be clear before construction begins.
Related: Mortgage declined? Start here · Mortgage Knowledge Centre · Real Estate Centre · Updates & Rules Centre
Would a second opinion help before you commit?
Send Rajiv the property, deadline, financing concern and the documents already available. He can identify the missing questions, compare practical mortgage routes and explain the next step in plain language.