Building a new garage or turning an old one into a functional space is one of the most valuable upgrades for Ontario homeowners. But the total cost can vary widely based on garage type, size, finishes, and local permit rules.
This guide breaks down garage construction costs in Ontario, including price ranges, permit fees, cost-per-size tables, breakdowns by materials and labour, and real project examples to help you plan your budget confidently.
Average Garage Construction Cost in Ontario: Prices & Permits
Garage construction costs vary across Ontario depending on the city, local permit fees, labour rates, and design complexity. In high-density urban areas like Toronto and Etobicoke, prices tend to be slightly higher because of tighter zoning rules, limited lot space, and more complex permit requirements. Suburban regions such as Aurora, Markham, Richmond Hill, Newmarket, Pickering, and Mississauga often offer more flexibility for garage size, placement, and materials, which helps keep overall costs predictable.
On average, homeowners across these cities can expect a typical garage project to fall between $19,900 and $78,000+, depending on the size (single vs. double), whether the garage is attached or detached, and the level of finishing required. This broad range reflects the diversity of architectural styles, lot conditions, and upgrade options across Ontario.
Here’s a general breakdown based on project level:
| Type of Garage | Approx. Cost Range | Description |
| Basic Single Garage | $19,900–$34,000 | Entry-level build, standard materials, basic slab |
| Double Car Garage | $30,000–$58,000 | Most popular choice; comfortable space for 2 cars |
| Detached Garage with Storage/Workshop | $35,000–$65,000 | Includes workspace, electrical upgrades |
| Attached Garage Addition | $40,000–$70,000 | More complex due to home tie-in & insulation |
| Garage with Loft / Partial Second Floor | $50,000–$85,000+ | Premium storage, office, or hobby room |
| Garage Conversion to Living Space | $40,000–$95,000+ | Insulated legal living area, egress, HVAC |
Cost by Garage Type (Detached garages VS Attached garages)
The type of garage you choose has a major impact on overall cost. Single-car garages are the most affordable, offering basic shelter and storage with minimal structural or electrical needs. Double-car garages cost more but provide better functionality, space for two vehicles, and room for shelving or small workshop setups. Detached garages typically come at a higher price because they require a separate foundation, independent electrical lines, and full exterior finishing. Attached garages must integrate with the home’s structure and meet fire-separation requirements, adding some complexity but offering greater convenience and insulation.
Single Car Garage Cost in Ontario
- Size: 12′ x 20′ or 14′ x 22′
- Cost: $20,000–$34,000
Good for compact lots and essential storage.
Double Car Garage Cost in Ontario
- Size: 20′ x 20′ or 22′ x 24′
- Cost:$30,000–$58,000
Ideal for families needing extra space
Detached Garage Cost
- Cost: $35,000–$65,000
- Usually pricier due to new slab, framing, separate electrical, and roofline.
Attached Garage Addition Cost
- Cost:$42,000–$70,000
- Costs more because it must tie structurally into the home.
Garage Cost per Size (Ontario 2026)
Garage size directly influences the total construction cost because larger garages require more concrete, framing materials, roofing, insulation, and labour. A compact 12×20 structure is suitable for basic needs, while sizes like 20×20 or 22×24 offer the extra space most homeowners prefer for storage, tools, and comfortable vehicle access. Bigger garages also give you the option to add workbenches, taller walls, or a small workshop area. As size increases, costs scale proportionally with the additional square footage, which is why most Ontario garage builds come in at roughly $80–$140 per sq.ft. Larger footprints also provide the best return on investment, as they enhance functionality and future-proof the home.
| Garage Size | Average Cost | Notes |
| 12×20 (240 sq.ft.) | $19,900–$32,000 | Most basic build |
| 14×22 (308 sq.ft.) | $23,000–$36,000 | Slightly more interior room |
| 20×20 (400 sq.ft.) | $34,000–$52,000 | Standard double |
| 22×24 (528 sq.ft.) | $38,000–$58,000 | Larger double |
| 24×30 (720 sq.ft.) | $48,000–$75,000 | With workshop/storage |
Cost per sq.ft. for garage construction:
$90–$140 per sq.ft. (Ontario average)
Garage Building Detailed Cost Breakdown (Material + Labour)
Garage construction includes several components that shape the final budget. The project begins with the concrete slab, which may need excavation or grading depending on site conditions. Framing determines the structure’s strength, while roofing and exterior finishes must match the home’s style and durability needs. Electrical work ranges from basic lighting to EV-ready or workshop-level wiring. If the garage is attached or intended for year-round use insulation and interior finishing become essential. Each element carries its own cost range, collectively determining the total investment.
Here is a realistic breakdown of where your budget goes in a garage build:
| Component | Cost Range | Notes |
| Foundation / Concrete Slab | $4,000–$11,000 | Thickness, drainage, rebar |
| Framing (Walls & Roof) | $5,000–$16,000 | Wood prices vary |
| Roofing (Shingles/Metal) | $2,500–$8,000 | Matching home increases cost |
| Exterior Siding / Brickwork | $3,000–$12,000 | Vinyl < Fiber Cement < Brick |
| Garage Door (Single/Double) | $1,200–$4,800 | Insulated doors cost more |
| Entry Doors & Windows | $900–$3,800 | For ventilation & lighting |
| Electrical Work | $1,200–$4,500 | Lighting, plugs, 240V for EV |
| Insulation (If Heated) | $1,500–$5,000 | Required for attached garages |
| Interior Finishing | $1,500–$7,500 | Drywall, mudding, paint |
| HVAC / Heating (Optional) | $1,500–$5,000 | Required for conversions |
| Permits | $350–$2,000 | City dependent |
Garage Permit Costs in Ontario
Permits vary by municipality, but here are common ranges:
| Permit Type | Cost |
| Garage Construction Permit | $350–$1,500 |
| Zoning Review Fee | $100–$450 |
| Demolition (if applicable) | $75–$350 |
| Development Charges (rare) | $0–$3,000+ depending on city |
Some cities (Toronto, Mississauga, Markham) may require:
- Setback checks
- Lot coverage limits
- Stormwater management
- Fire separation standards for attached garages
What Affects Garage Construction Cost
Several factors influence garage construction pricing in Ontario. Size and layout are the biggest drivers, followed by whether the garage is attached or detached. Material choices like premium siding, insulated doors, or upgraded roofing also affect cost. Electrical requirements, EV chargers, or workshop outlets increase labour time. Site conditions, including slopes or difficult access, can raise excavation and preparation costs. Finally, city zoning and permit rules impact design and engineering needs, making them an important part of project budgeting.
1. Size & Dimensions
Biggest cost factor larger footprint = more materials + labour.
2. Attached vs. Detached
Attached garages are more expensive due to structural tie-ins.
3. Materials Chosen
Siding type, insulation, and roofing dramatically affect the price.
4. Electrical & Heating
Workshops, EV chargers, or heated garages push costs upward.
5. Permit Restrictions
Some cities require engineered drawings or environmental rules.
6. Site Conditions
Sloped lots, excavation, or poor soil adds cost.
Garage Conversion Cost (Garage → Living Space: Office, Gym, or Garage Rental ADU)
Converting a garage into a livable space is significantly more complex than basic garage construction because it must meet the same building standards as interior rooms. This includes full insulation, vapor barriers, proper HVAC integration, safe electrical systems, and fire-rated walls requirements that often bring the total into the $40,000–$95,000+ range. Depending on whether the space becomes a bedroom, office, gym, or rental suite, homeowners may also need plumbing upgrades, new windows for natural light and egress, and flooring systems that meet code. Garage conversions offer excellent long-term value by adding functional square footage to the home, but they require careful planning to meet Ontario’s building guidelines.
If you’re converting the garage into a legal living area:
Average Conversion Cost:
$40,000–$95,000+
Includes:
- Insulation
- Windows & egress
- HVAC
- Flooring
- Electrical
- Drywall
- Plumbing (if adding bath)
- Permit upgrades (fire rating, zoning compliance)
Conversions are more expensive because you’re essentially creating interior living space with higher building-code requirements.
Real Ontario Garage Project Examples
Example 1 — Basic Single Garage
- Size: 12×20
- Total Cost: $22,500
- Included: slab, framing, roof, siding, standard door, basic electrical
Example 2 — Double Detached Garage
- Size: 20×22
- Total Cost: $38,000
- Included: upgraded shingles, lighting, outlets, insulated door
Example 3 — Garage with Small Workshop
- Size: 24×30
- Total Cost: $55,500
- Included: insulation, heater rough-in, 240V outlet, workbench area
Example 4 — Garage Conversion to Bedroom + Office
- Size: 420 sq.ft.
- Total Cost: $70,000
Included: interior walls, HVAC, flooring, egress window, drywall
How to Estimate Your Garage Budget (Simple Formula)
Use this quick calculation:
Garage Size (sq.ft.) × $90–$140 = Rough Estimate
Example:
480 sq.ft. (Double Garage)
→ 480 × $100 average = $48,000
Add:
- Electrical upgrades +$1k–$4k
- Insulated doors +$800–$1,500
Higher-end siding +$3k–$6k
Final Thoughts + Free Estimate
Garage construction is one of the most value-boosting upgrades Ontario homeowners can make. Whether you want a simple storage space, a full double garage, or a workshop, understanding the cost factors helps you plan without surprises.
