As a mortgage agent who underwrites mortgages, I’ve come across countless applications where homeowners and investors alike want to leverage rental income from basement suites or converted spaces to boost their borrowing power. It’s a smart move in theory, but the moment I hear the words “non-conforming apartment,” the conversation becomes more nuanced. If you’re hoping to use income from a non-conforming unit to qualify for a mortgage, here’s what you need to know.
What is a Non-Conforming Apartment?
How Prime Lenders View Non-Conforming Income
What is a Non-Conforming Apartment?
A non-conforming apartment is a rental unit that does not meet current municipal zoning, building, or fire code regulations. Common examples include:
- Basement apartments without the required ceiling height (typically 6’5″ or higher in Ontario)
- Secondary units without separate entrances, adequate egress, or proper fire separation
- Garage or attic conversions completed without permits
These units are often rented informally and generate income, but they haven’t been legalized by the city or town. From a mortgage perspective, this creates a gray area.
How Prime Lenders View Non-Conforming Income
Canada’s major banks and credit unions operate under stringent underwriting rules. As a rule of thumb, prime lenders will not recognize rental income from a non-conforming unit when qualifying a borrower. This is because the income source is considered unstable and potentially illegal, and insurers like CMHC, Sagen, and Canada Guaranty do not allow it.
Even if you have a long-term tenant and reliable monthly rent deposits, if the unit isn’t legal, you won’t be able to use that income with most A-lenders.
Enter the Alternative Lenders
This is where alternative lenders (B-lenders) offer a valuable option. They are often more flexible and are willing to take a more common-sense view. Many of them will accept income from non-conforming apartments, particularly if you can demonstrate that the unit is:
- Self-contained
- Has a separate entrance
- Generates consistent rental income
In these cases, you may be asked to provide documentation such as:
- A signed lease agreement
- Bank statements showing consistent rent deposits
- An appraisal report including a market rent estimate
Each lender’s policy differs, so working with a broker who knows which lenders are open to these scenarios is essential.
Comparing Rates
Let’s compare rates among the different types of lenders. When it comes to discussing rates, understand that rates, like the prices on stocks on any stock market, are always moving; so this is really a snapshot in time.
Monoline Lenders
Monoline lenders in Canada—such as First National, MCAP, RFA, CMLS, and others—are closer in policy to prime banks than they are to alternative (B) lenders when it comes to underwriting.
Most monoline lenders do not accept rental income from non-conforming apartments.
To use rental income, monoline lenders typically require:
- A legal secondary suite (conforming to zoning, building, and fire codes)
- Lease agreement
- T1 General with Statement of Real Estate Rentals (T776) or
- Appraisal with market rent estimate (for conventional files)
However, they often offer the best rates so they should be the first place you shop.
Credit Unions
In general, credit unions tend to follow more conservative underwriting guidelines—similar to banks and monoline lenders—especially the larger, more regulated ones (like Meridian, DUCA, or Alterna).
Most credit unions will not accept rental income from non-conforming apartments unless the unit meets local zoning and building codes.
However, the key difference with credit unions is this:
They’re Not All the Same
Unlike federally regulated banks and monoline lenders, credit unions are provincially regulated and often have their own internal lending policies and discretion. This allows some of them to:
- Make case-by-case exceptions for strong borrowers
- Use common-sense underwriting when there is strong rental history, proper documentation, and good credit
- Rely more on internal adjudication than rigid insurer guidelines, especially on uninsured deals
Scenarios Where a Credit Union May Consider Non-Conforming Income
Some credit unions may accept non-conforming rental income if:
- The borrower has strong credit, low total debt service, and ample net worth
- The unit is self-contained, has its own entrance, and shows consistent rental income via leases or bank deposits
- The mortgage is conventional (not insured or insurable)
- The deal is held on balance sheet, rather than being securitized or underwritten to CMHC/Sagen standards
Documentation They Might Consider:
- Lease agreement (even month-to-month)
- Bank statements showing 3–12 months of rental deposits
- Letter from a property manager or tenant
- Market rent letter from an appraiser
However, credit unions often are the second best place for rates when rental income is being considered, so they should be another place you should shop.
Alternative Lenders
Alternative lenders—also known as B-lenders—are the most flexible and most likely to accept rental income from non-conforming apartments when underwriting a mortgage in Ontario.
NOTE: I don’t mean private lenders when I am speaking of Alternative lenders in this context.
If your home has a basement suite, attic unit, or other space that generates income but doesn’t meet municipal zoning or building code requirements, alternative lenders are your best path forward.
How Alternative Lenders Think
Unlike banks and monoline lenders, alternative lenders don’t need to follow mortgage insurer guidelines (CMHC, Sagen, Canada Guaranty), and many of their mortgages are held on balance sheet. That gives them the freedom to assess:
- The income stream (is it stable and provable?)
- The unit’s setup (is it self-contained, even if not legal?)
- The borrower’s profile (credit score, equity, total debt servicing)
They use a common-sense underwriting approach, not a rules-based formula.
When Will Alternative Lenders Accept Income from a Non-Conforming Apartment?
They’ll often say yes when:
- The unit is self-contained (e.g., kitchen, bathroom, separate entrance)
- There is a signed lease or long-standing tenant
- You can show consistent rental deposits (usually 3–12 months)
- The deal is conventional (20%+ down payment)
- The borrower has reasonable credit and provable income for the rest of the application
Some may even accept market rent appraisals in place of lease agreements.
Common Documentation Requirements
Alternative lenders will typically accept any two or more of the following:
- Signed lease agreement
- Bank statements showing rental deposits
- Appraisal with market rent schedule (Form 1007 or similar)
- Letter from tenant or affidavit
- T776 (Statement of Real Estate Rentals) from recent tax filings
However, alternative lenders rates are generally 1% higher when rental income is being considered compared to prime lenders like monoline lenders, banks, and certain credit unions, but in particular situations, they may be the only type of lender willing to include this kind of rental income.
No Separate Entrance
When it comes to non-conforming apartments without a separate entrance, alternative lenders are your best—and often only—chance of getting the rental income considered in a mortgage application. That said, the absence of a separate entrance is a significant red flag, and here’s why.
Why a Separate Entrance Matters
A separate entrance is one of the minimum safety and privacy features lenders (and municipalities) look for to define a unit as “self-contained.” Without it, the apartment is seen as:
- Functionally part of the main dwelling
- More difficult to evict or separate
- A potential fire code and insurance liability issue
Even alternative lenders, who are more flexible with non-conforming units, will pause if there is no independent access to the rental space.
What Some Alternative Lenders Might Still Consider
Some B-lenders may still allow the rental income if:
- The renter has a long-standing history and a formal lease
- Rent is provable through deposits or tax documents (T776)
- The unit has a kitchen, bathroom, sleeping area, and some form of privacy
- The deal has strong equity (e.g., 25–35% down payment)
- The borrower has good credit and low other liabilities
In this case, the lender might treat the unit more like a boarder or lodger scenario, or ask for a market rent appraisal with a “room rental” valuation.
What Lenders May Do Instead
- Apply a rental offset (e.g., 50%) instead of using the full rental income
- Limit the amount of rental income they’ll recognize
- Increase the required debt servicing cushion or request additional income support
My Recommendation
If the apartment lacks a separate entrance, here’s how to move forward:
- Gather documentation: Lease, rent deposits, appraisal with room rent (if applicable)
- Work with lenders that manually underwrite: Not all B-lenders will allow this—focus on Equitable Bank, Optimum, Haventree, etc.
- Set expectations: The income might only be partially included or may require a higher equity position
- Consider adding a separate entrance: It’s often a simple renovation that significantly boosts both mortgage qualification and resale value
Risks and Considerations
Before moving forward, it’s important to understand the risks of using income from a non-conforming apartment:
- Insurance complications: If the unit isn’t legal, some insurance policies may not cover damages or liability.
- Municipal enforcement: The city could order the tenant to vacate or force you to remove the unit entirely.
- Resale complications: Buyers may have difficulty obtaining a mortgage, which could impact your home’s marketability.
Steps Toward Legalization
If you’re serious about using this rental income long-term, consider legalizing the unit. This process typically includes:
- Verifying zoning to ensure a second unit is permitted
- Obtaining permits and submitting floor plans
- Completing renovations to meet building and fire code standards
- Undergoing municipal inspections
- Registering the unit, where applicable
Legalizing the unit not only helps with financing, but also adds long-term value and security to your property.
My Final Thoughts
Using rental income from a non-conforming apartment is possible — but not with every lender. If you’re planning to include it as part of your mortgage application in Ontario, contact me to discuss your options so you can understand the difference between A-lenders and alternative for your given situation.
Documentation, stability of the rental stream, and the physical setup of the unit all factor into whether that income can be used. And if the ultimate goal is to maximize financing options and minimize risk, legalizing the unit is a wise long-term investment.
In today’s real estate market, every dollar of qualifying income counts. Just make sure it’s coming from a source your lender will recognize.
