Garden Suite Costs in Toronto, Explained
A garden suite is a separate backyard home, also called an additional residential unit (ARU) or detached accessory dwelling unit. In Toronto in 2026, the all-in turnkey price for one runs $160,000 to $380,000. That range is wide because lots are different. A 40 sqm studio on an open lot with good services sits near the bottom. A 60 sqm suite with a loft on a ravine lot with an old hydro service sits near the top.
What does a garden suite cost in Toronto by size?
For a detached site-built suite, expect $160,000 to $240,000 at 40 sqm and $220,000 to $380,000 at 60 sqm. Per square metre that works out to roughly $4,000 to $6,300 all-in, higher on small suites because kitchens, bathrooms and mechanical systems cost the same whatever the size. Toronto Building permit fees, design and engineering are part of the total. Prefab-hybrid suites save $20,000 to $40,000, and garage conversions can start at $120,000 when the existing structure is sound.
Which rules affect the cost under By-law 574-2022?
By-law 574-2022 and Zoning By-law 569-2013 set the size cap (60 sqm, or 40 sqm on narrower lots), separation from the main house, setbacks and fire access. Those rules shape the footprint and so the price. Overlays add cost: TRCA regulated areas can require a geotechnical review, the Tree Protection By-law can require helical piles near root zones, and a Heritage Conservation District can call for specific cladding. A minor variance at the Committee of Adjustment adds fees and about two months.
Who gives fixed-price garden suite quotes in Toronto?
Many builders quote a range and adjust it during construction through allowances and change orders. We issue a written fixed price after the feasibility report, because by then we know the lot, the envelope and the utility situation. Our founder, Dmitri Varga, P.Eng and BCIN Part 9, reviews every quote before it goes out.
How We Build Your Cost Estimate
1. Free consult
A short call or site walk. We ask about goals (rental, family, office or retirement), lot width, lane access, garage and timeline, and give you a realistic range.
2. Written feasibility report
Our garden suite site evaluation confirms eligibility, measures the envelope and checks soil, access and utility capacity. It costs $1,200 to $2,800 with zero deposit, and it is what makes a fixed price possible.
3. Fixed-price quote
Within 2 weeks of the report, you get a written CAD quote showing hard and soft costs, material allowances, exclusions and the 5-stage draw schedule.
4. Contract with written change control
10% at contract, then draws at permit, foundation, framing, finishes and occupancy. Any change needs your written approval and a written price before work starts.
Garden Suite Cost Breakdown (60 sqm Example)
| Cost item | Typical range | Notes |
|---|---|---|
| Feasibility, design and engineering | $10,000 - $20,000 | Includes energy compliance |
| Permits and agency fees | $4,000 - $10,000 | City fees plus expeditor service |
| Foundation | $18,000 - $40,000 | Slab, shallow frost-protected or helical piles |
| Structure and envelope | $60,000 - $95,000 | Framing, roof, windows, insulation, cladding |
| Mechanical and electrical | $30,000 - $50,000 | Heat pump, HRV, 100-amp sub-panel, plumbing |
| Utility connections and upgrades | $12,000 - $45,000 | Toronto Hydro, Toronto Water, sewer, Enbridge |
| Interior finishes | $40,000 - $80,000 | Kitchen, bath, flooring, millwork |
| Site work and landscaping | $8,000 - $20,000 | Paths, grading, restoration |
| Total turnkey | $220,000 - $380,000 | Before HST |
What Drives the Price on a Toronto Lot?
Utility upgrades. Older homes in Riverdale, Leslieville and East York often have a 60-amp electrical service or a 1/2 inch galvanized water line. A Toronto Hydro service upgrade or new Toronto Water line can add $12,000 to $30,000.
Foundation choice. A frost-protected shallow foundation on an open lot is the least costly. Helical piles cost more but protect tree roots and work on poor soil or tight access.
Access. Narrow side yards mean hand-carrying materials or booking a crane and a street occupancy permit.
Size and storeys. A loft or second storey adds structure and stairs, but leaves more yard.
Finish level. Our standard spec meets Toronto Green Standard Tier 1. Upgraded or premium finishes add roughly 12 to 25 percent to construction.
The cheapest garden suite is the one you only design once
Redrawing a suite after a Zoning Examiner rejection costs $3,000 to $8,000 in fees and 8 to 12 weeks of carrying costs. Measuring the envelope first is the single best cost control.
Cost by Build Type
| Build type | Typical Toronto range | Page |
|---|---|---|
| Detached site-built | $180K - $340K | Detached garden suites |
| Prefab-hybrid | $140K - $240K | Prefab garden suites |
| Attached | $160K - $280K | Attached garden suites |
| Garage conversion | $120K - $220K | Garage conversions |
| Laneway house | $200K - $380K | Laneway houses |
Does a Garden Suite Pay for Itself?
Toronto garden suites typically rent for $2,200 to $3,400 a month. A $280,000 suite renting at $2,800, after a vacancy allowance and about $4,500 a year in taxes, insurance and upkeep, nets roughly $27,750 a year, which is a payback of about 10 years before financing. Our rental income suite service shows how layout and finishes affect rent. For the full list of service prices in one place, see our pricing page.
