Legal Basement Apartment Permit Drawings in Ontario

Ontario Design Studio prepares BCIN-certified permit drawings for legal basement apartment conversions across Ontario. Basement apartments (also called second units or secondary suites) are one of the most popular residential projects in the GTA — and one of the most regulated. Our team handles every OBC requirement including zoning verification, fire separation details, egress compliance, energy code requirements, and municipal submission support.

What You Need for a Legal Basement Apartment in Ontario

Converting a basement into a legal dwelling unit requires compliance with the Ontario Building Code, your municipality's zoning bylaw, and fire safety regulations. Here are the key requirements as of 2026:

Ceiling Height: Minimum 1.95m (6'5") in all habitable rooms — if your ceiling is too low, underpinning may be required
Fire Separation: 45-minute fire resistance rating between units using fire-rated drywall, doors, and sealed penetrations
Egress Windows: Minimum 0.35 m² unobstructed opening in each bedroom, with a minimum dimension of 380mm
Smoke & CO Alarms: Interconnected alarms on every level of each unit
Separate Entrance: Interior shared hallway or exterior separate entrance
Kitchen & Bathroom: Full kitchen and bathroom facilities required for a legal dwelling unit
Heating: Independent heating system or zone for the basement unit
Parking: Requirements vary by municipality — many have been reduced or eliminated under Ontario's 2023 housing policy

For a complete breakdown, read our 2026 legal basement apartment requirements guide.

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Our Basement Permit Drawing Package

Our standard basement apartment permit package includes everything your municipality needs for a complete submission:

Site plan showing existing building, lot boundaries, and parking
Existing and proposed basement floor plans with room dimensions
Fire separation details — 45-minute fire rating between units, sealed penetrations, fire-rated doors
Egress window schedule with minimum sizes per OBC Section 9.9.10
Cross-section showing ceiling heights and structural assembly
Energy compliance form SB-10 or SB-12
Schedule 1 designer information form
Zoning compliance summary confirming conformity with municipal bylaw

Basement Apartment Costs

BCIN designer fees for basement apartment drawings range from $2,000 to $4,000. Municipal permit fees are additional and vary by municipality. See our complete pricing guide for detailed cost breakdowns.

Cities We Serve for Basement Permits

We prepare legal basement apartment drawings across Ontario, with specialized experience in:

Toronto — including Scarborough, Etobicoke, and North York
Mississauga — one of the highest-demand cities for basement apartments
Brampton
Markham
Vaughan
Hamilton
Oakville
Burlington

View all service areas →

Related Resources

Frequently Asked Questions

Do I need a permit for a basement apartment in Ontario?

Yes. Converting a basement into a legal apartment in Ontario requires a building permit. You'll need BCIN-certified drawings showing fire separation, egress windows, ceiling heights, smoke/CO alarms, and energy compliance. Without a permit, the suite is considered illegal and may affect your insurance and resale value.

What is the minimum ceiling height for a basement apartment in Ontario?

The Ontario Building Code requires a minimum ceiling height of 1.95 metres (6 feet 5 inches) in all habitable rooms of a basement apartment. If your existing ceiling is lower, basement underpinning or bench footing may be required to meet this standard.

How much does it cost to get legal basement apartment drawings in Ontario?

BCIN designer fees for basement apartment permit drawings typically range from $2,000 to $4,000 in Ontario, depending on the complexity of your project. This includes the site plan, floor plans, fire separation details, egress window schedule, energy compliance form, and Schedule 1.