A second suite can help pay the mortgage.
Most homeowners who call us aren’t building a portfolio. They’re paying a mortgage on the house they live in and want rental income, or space for a parent or adult child, to help carry it. A basement apartment or garden suite is the most direct way to do that on a property you already own.
Rent covers 36% of your monthly costs.
Illustrative only, not a quote. Rent ranges are typical for Hamilton, Burlington, Brantford and Paris. Your mortgage, tax, and achievable rent depend on your property.
- Mortgage
- $3,600
- Property tax
- $417
- Insurance and upkeep
- $250
- Monthly costs
- $4,267
- Rent
- −$1,550
- You pay
- $2,717/mo
Why do homeowners add a unit?
Two reasons, almost every time: rental income to help carry the mortgage, or a place for family close by.
- 01
Rental income to offset the mortgage
A legal, permitted unit rents for real money, month after month, and that rent goes straight at your carrying cost. It’s the single biggest lever most homeowners have over their monthly budget without moving.
- 02
A place for family
A parent who needs to be close but not under the same roof. An adult child saving for their own place. A caregiver. The unit doesn’t have to be rented to a stranger to be worth building.
What does it cost, and what does it earn?
Typically $80,000–$175,000 for a basement apartment and $200,000–$300,000+ for a garden suite, all in, with a legal unit often adding value once it’s on title.
Basement apartment
Garden suite
Wide ranges on purpose. Hamilton, Burlington, Brantford and Paris don’t all rent the same, and neither does a fresh renovation versus a dated one. Treat these as a starting point for your own math, not a promise. See Cost & Financing for what drives your number up or down.
How do homeowners pay for it?
Most stack two or three of these sources, so you may not need the full cost in cash.
From savings$0
Tap a source to switch it on or off. Illustrative only: programs, rates and eligibility change, and a grant or tax credit usually arrives after you’ve paid, not before.
HELOC against your home
Most lenders will advance up to 65% of your home’s appraised value on a line of credit, or up to 80% combined with your existing mortgage. For a $150,000–$200,000 build, this alone often covers most of it.
CMHC Refinance Program
The current main federal option: refinance your existing mortgage to access up to 90% of your home’s post-renovation value, specifically to build a secondary suite. Confirm current terms with a lender before counting on it.
Multigenerational Home Renovation Tax Credit
A one-time refundable federal credit worth up to $7,500 (15% of up to $50,000 in eligible costs), if the unit lets a senior or a relative eligible for the disability tax credit live with family. One claim per lifetime, and not for a unit rented to a stranger.
Municipal grants, where they exist
Hamilton’s ADU grant (70% of eligible costs, up to $40,000 per unit) reached its funding limit and is closed to new applications. Ontario Renovates offers a forgivable loan of up to $25,000. Programs change often, so we confirm what’s live for your address.
We’re not a lender or a financial advisor. This is what homeowners typically stack together, not financial advice. Talk to a mortgage broker or accountant about what fits your situation, and check current program rules before deciding.
Sources, as of October 2026: OSFI Guideline B-20 (HELOC limits); Canada Revenue Agency, Multigenerational Home Renovation Tax Credit; City of Hamilton, Additional Dwelling Unit and Multi-Plex Housing Incentive Program (amended October 9, 2025).
For a homeowner, it comes down to cost versus privacy.
Basement apartment
Working inside a structure that already exists, usually the faster, cheaper path to rent coming in.
Garden suite
Costs more and takes longer, but a fully separate unit for a parent or renter, no shared entrance or walls.
Full comparison: Basement Apartment vs. Garden Suite
Same four stages, on your property.
Feasibility check
Does your basement or lot qualify, and which grants realistically apply?
Permit drawings
Permit drawings done in-house, not subbed out.
Permit submission
Filed with your municipality on your behalf.
Approval and build
Permit issued, construction begins, rent starts.
Pick the question closest to yours.
We’ll tell you what applies to your address.
What your property qualifies for, and which grants or financing actually apply, before you spend a dollar on drawings.