Garden Suite Financing in Ontario: How to Fund a Laneway Home or Secondary Suite
Ontario has made it far easier to add a second unit to your property. Most residential lots can now hold up to three units as of right, and Toronto, Ottawa, Hamilton, and many other municipalities permit garden suites and laneway homes. The zoning problem is largely solved. The money problem is not.
Garden suite financing in Ontario is where most of these projects stall. A detached backyard unit routinely costs $350,000 or more to build, the federal government's much-promoted 2 percent loan covers only a fraction of that, and banks underwrite a half-finished backyard building very differently than a house purchase. This guide covers what garden suites, laneway homes, and secondary suites actually cost to build in 2026, the government programs that can help, the refinance, HELOC, and construction financing options in between, and how lenders assess these projects.
Garden suite, laneway home, or secondary suite: why the label matters to your lender
The terms get used interchangeably, but they describe different structures, and the differences flow straight into cost and financing.
- Secondary suite: a self-contained unit inside your existing house, most often a basement apartment with its own entrance, kitchen, and bathroom.
- Laneway home (or laneway suite): a detached unit built where your property backs onto a public laneway, common in older Toronto neighbourhoods.
- Garden suite: a detached unit in the rear yard of a lot that does not border a laneway. Toronto permitted these city-wide under By-law 101-2022 in February 2022, and most Ontario municipalities now allow some version of them.
All three fall under the umbrella term accessory dwelling unit, or ADU, and under Ontario's additional residential unit rules, which allow up to three units on most urban residential lots. Provincial legislation, including Bill 23, also removed development charges on a second, third, or fourth unit in many municipalities. Toronto formalized that exemption in By-law 1137-2022, which can save a builder tens of thousands of dollars in fees.
The label matters for financing. A basement secondary suite is a renovation inside an existing, already-mortgaged structure. A garden or laneway suite is new construction: excavation, foundation, utility connections trenched across the yard, and a standalone building an appraiser has to value before it exists. Lenders price those situations differently, and so do the programs below.
What an ADU actually costs to build in Ontario in 2026
Older articles still circulate figures like $150,000 to $200,000 for a garden suite. Current Greater Toronto Area pricing is well above that, and a stale budget is the fastest way to end up mid-build with no financing room left.
A 2026 Toronto cost guide from design-build firm Maserat puts garden suite construction at $400 to $550 per square foot and laneway suites at $450 to $600 or more, depending on finishes. For a typical 600 square foot one-bedroom unit, that is $240,000 to $330,000 in hard costs alone.
| Project type | Typical hard cost | Realistic all-in range |
|---|---|---|
| Basement secondary suite conversion | Varies widely with layout and code upgrades | Roughly $100,000 to $200,000 for a full legal conversion |
| Garden suite, 600 sq ft | $240,000 to $300,000 | $365,000 to $525,000 including soft costs |
| Laneway suite, 600 sq ft | $270,000 to $330,000 | $400,000 to $550,000 including soft costs |
The all-in figures include the items first-time builders forget: design and engineering ($15,000 to $40,000), permits and fees ($5,000 to $15,000), utility servicing ($15,000 to $40,000 or more), site preparation, and a 10 to 15 percent contingency. Servicing distance is the most variable line and can add tens of thousands of dollars on its own.
A detached build is therefore a construction financing problem, not a renovation you put on a credit line, and the budget needs a funded contingency; lenders would rather structure one up front than rescue an over-budget project later.
The Canada Secondary Suite Loan Program: $80,000 at 2 percent
The headline federal support is the Canada Secondary Suite Loan Program. As announced in the 2024 Fall Economic Statement, it offers homeowners up to $80,000 at a 2 percent interest rate over a 15-year term, doubled from the $40,000 limit in Budget 2024, which set aside $409.6 million through CMHC.
The intent is cheap, patient capital for owner-occupants adding a legal, self-contained, long-term rental suite to the home they live in. Short-term rentals do not qualify.
Two honest caveats. First, the application rollout has lagged the announcement, so verify current status on the Government of Canada and CMHC websites before budgeting around it. Second, $80,000 can carry a large share of a basement conversion but is roughly 15 to 20 percent of a detached garden suite budget, so for a backyard build treat it as a low-cost layer in the capital stack, not the plan itself.
At 2 percent over 15 years, an $80,000 loan costs about $515 per month, which even a modest basement suite rent should cover.
Refinancing to 90 percent: the CMHC insured refinance for secondary suites
The quieter but more powerful change arrived on January 15, 2025. The federal government now allows insured mortgage refinancing specifically to build secondary suites, and it lends against the value of your home after the suite is built rather than before.
Under the CMHC program rules, the key parameters are:
- Refinance up to 90 percent of the as-improved value, versus the standard 80 percent conventional limit.
- The as-improved value must be under $2 million.
- Amortization up to 30 years.
- Up to four units, with you or a close relative living in one of them.
- Minimum credit score of 600, with debt ratios capped at 39 percent GDS and 44 percent TDS at the stress-test rate.
- The suite must be self-contained, legal under local bylaws, and a long-term rental.
- Funds are restricted to construction costs, equity take-out is not permitted, and CMHC approval is required before construction starts.
The fine print that matters most: the lending value is the lesser of the as-improved appraised value or the as-is value plus the documented cost of improvements, so you cannot manufacture borrowing room with an optimistic future appraisal. You will also pay a mortgage insurance premium on the refinanced amount, which is meaningful at high loan-to-value ratios.
Worked simply: on a home with an as-improved value of $1.2 million, the program allows total financing up to $1.08 million. If your current mortgage is $500,000, that is up to $580,000 of construction room before premiums, enough for most garden and laneway builds if your income qualifies.
HELOCs, second mortgages, and other ways to raise the build budget
Not every project fits the insured route, and not every owner wants to break a low-rate mortgage and pay the penalty. The conventional toolkit:
- Home equity line of credit. Federally regulated lenders cap the revolving portion of a HELOC at 65 percent of your home's value, within an 80 percent combined limit. You draw as invoices come due and pay interest only on what you have used, but the rate floats and the limit may not reach a detached build budget. Our guide to HELOCs and home equity loans in the GTA compares the two structures.
- Conventional cash-out refinance. Up to 80 percent of current value, with no requirement that funds go to construction. Simple, but it reprices your whole mortgage and triggers a prepayment penalty if you break mid-term.
- Second mortgage. A separate loan behind your existing first mortgage, which stays untouched. For owners sitting on a low fixed rate until 2027 or 2028, a second mortgage in Ontario is often the cheaper total-cost path, even at a higher nominal rate, because it avoids the penalty and repricing.
- The Multigenerational Home Renovation Tax Credit. A refundable federal credit worth 15 percent of up to $50,000 in eligible costs, a maximum of $7,500, when the suite houses a senior or an adult eligible for the disability tax credit.
- Municipal incentives. Some municipalities offer forgivable loans for affordable second units through provincially funded renovation programs; amounts and income caps vary by city.
These layers stack. A homeowner might combine a HELOC for early soft costs, the federal 2 percent loan if available, and a refinance at completion, provided the sequencing is planned before construction starts.
When the bank says no: private construction financing for ADU projects
Many ADU projects do not fit the insured or bank box: the owner is self-employed with income that looks thin on paper, debt ratios fail the stress test even though the finished suite's rent would fix them, credit took a hit, the property already carries financing near 80 percent, or the project is underway and over budget, which most institutional lenders will not touch.
This is where private construction financing does its job. A private lender or mortgage investment corporation lends primarily against the property's equity and the as-improved value of the project rather than against payroll income. Typical Ontario terms run 8 to 12 percent interest-only on one-year terms, with lender and broker fees commonly in the 2 to 4 percent range, advanced in staged draws tied to milestones: foundation, framing and lock-up, mechanical rough-in, completion. Each draw follows a progress inspection. Our overview of private construction loans in Ontario explains draw schedules, holdbacks, and costs in detail.
The structure only makes sense with a defined exit. For ADU projects the exit is usually clean: once the suite is complete and rented, the property appraises higher and the owner refinances into bank or insured financing at a much lower rate, repaying the private loan. Twelve to eighteen months of higher-cost money buys the completed asset that qualifies for cheap money. Budgeting that bridge, including an interest reserve so payments do not strain cash flow mid-build, is the core discipline of how construction financing works in Ontario at any scale.
The rental income upside, and how lenders treat it
The reason any of this pencils is rent. The Rentals.ca National Rent Report put Toronto's average apartment asking rent at $2,577 as of July 2026, with the national average one-bedroom at $1,770. A well-built one-bedroom garden or laneway suite in a strong GTA location can plausibly rent in the $1,900 to $2,600 range, while basement suites typically sit lower.
Lenders treat that income in two distinct ways, and the difference decides approvals:
- Qualifying income. Most banks will count 50 to 100 percent of legal suite rent, existing or projected via an appraiser's market rent letter, in your debt service ratios. Policies differ enough that lender choice can decide whether the same borrower passes or fails.
- Project viability. Equity-based lenders look at rent through the exit lens: will the finished, tenanted property support the refinance that repays them?
Underwrite your own project the way a lender would: assume a vacancy and maintenance allowance, confirm the suite will be legal and registered where required, since lenders discount illegal-suite income, and stress your numbers against a lower appraisal. The as-improved rules cap lending at cost, so an over-budget build does not automatically create new borrowing room.
A worked example: financing a $350,000 laneway suite
This example is hypothetical, for illustration only. Suppose you own a Toronto home worth $950,000 with a $475,000 mortgage at a low fixed rate until 2028, and a builder quotes $350,000 all-in for a 600 square foot laneway suite expected to rent near $2,400 per month.
- Insured refinance route. As-improved value estimated at $1.15 million. Ninety percent is $1,035,000, which after the $475,000 mortgage leaves up to $560,000 of room, far more than needed. But refinancing means breaking the fixed rate, paying the penalty and insurance premium, repricing the full balance, and passing the stress test on the whole amount.
- Second mortgage or HELOC route. Keeps the first mortgage intact, but conventional limits (80 percent of the current $950,000 value, minus $475,000) cap proceeds around $285,000, short of the budget.
- Blended route. A construction-oriented second facility funds the build in draws; on completion, the owner refinances at renewal in 2028 against the improved, income-producing property. Bridge interest costs more, but no penalty is paid and the low first-mortgage rate is preserved until it expires anyway.
None of these is universally right. The cheapest sticker rate is not always the cheapest project, and the structure should be chosen before permits are issued, not after framing starts.
FAQ
Is the Canada Secondary Suite Loan Program open for applications?
The program was announced in Budget 2024 and enhanced in the 2024 Fall Economic Statement to offer up to $80,000 at 2 percent over 15 years, with launch planned for early 2025. Application details have rolled out slowly, so check the Government of Canada and CMHC websites for current status before counting on it.
How much does a garden suite cost to build in Ontario?
In the Toronto area, garden suites run about $400 to $550 per square foot in hard costs, and a 600 square foot unit typically lands between $365,000 and $525,000 all-in with design, permits, servicing, and contingency. Basement conversions are substantially cheaper, often $100,000 to $200,000 for a full legal suite.
Can I use future rental income from the suite to qualify for financing?
Often, yes. Many lenders count 50 to 100 percent of the legal suite's actual or appraiser-projected market rent toward your debt service ratios, though policies vary widely. Equity-based private lenders focus less on your ratios and more on the property's value and the project's exit plan.
What credit score do I need for the 90 percent insured refinance?
CMHC's program requires a minimum credit score of 600, debt ratios within 39 percent GDS and 44 percent TDS at the stress-test rate, an as-improved value under $2 million, and owner occupancy of one unit. Funds must go to suite construction, and approval is required before construction begins.
What happens if my post-build appraisal comes in lower than expected?
Insured lending uses the lesser of the as-improved appraised value or the as-is value plus documented costs, so a weak appraisal or an overrun can shrink your borrowing room. Build a 10 to 15 percent contingency into the financing, and identify a fallback such as a HELOC, second mortgage, or private facility before you break ground.
Do laneway homes qualify for the same programs as basement suites?
Generally yes. Federal programs apply to self-contained legal suites whether attached or detached, provided the unit is a long-term rental and local bylaws permit it. The practical difference is scale: detached builds cost several times more, so they rely far more on refinancing or construction financing than on the $80,000 federal loan.
Financing an ADU when your project does not fit the bank box
Garden suites and laneway homes are exactly the kind of project that can look marginal to a bank and solid to a lender that underwrites the property first. Strong equity, a realistic budget, a legal unit, and a clear refinance exit make a fundable file, even when the owner is self-employed, mid-build, or protecting a low-rate first mortgage.
Richview Capital is a Canadian mortgage investment corporation that provides alternative mortgage financing secured by real estate, including equity-based second mortgages and construction facilities structured around draws and a defined exit. If a bank has said no, or the structure on offer does not fit your project, we can tell you quickly whether your ADU plan is fundable and what it would cost.
Contact Richview Capital to talk through your garden suite or secondary suite financing before you break ground. A short conversation up front is cheaper than restructuring a half-built project later.
Next steps: Borrowers · Speak With Our Team · FAQ
Richview Capital MIC is a licensed Mortgage Investment Corporation (Mortgage Administrator License #13171). This article is educational information for Ontario homeowners, not legal, financial, or tax advice. Rates, fees, LTV limits, and approvals vary by file and underwriting, and published ranges are subject to change and are not an offer of credit.
