Egress Window Requirements in Ontario
Ontario Building Code specifications for basement bedroom windows. Size, height, and window well requirements explained.
What is an Egress Window?
An egress window is a window large enough for a person to escape through in an emergency, such as a fire. Ontario Building Code requires egress windows in all basement bedrooms to provide a second exit route if the basement stairs are blocked.
The Simple Rule
If you're adding a bedroom in your basement, you need an egress window. Rec rooms, home offices, and other non-bedroom spaces don't require egress windows, but bedrooms always do.
Ontario Building Code Egress Window Requirements
The Ontario Building Code (OBC) Section 9.7.1 specifies minimum egress window requirements for basement bedrooms:
Minimum Opening Size
- Unobstructed opening area: Minimum 0.35 m² (3.77 square feet)
- No dimension less than: 380 mm (15 inches) in any direction
- Measurement: The opening must meet these minimums when the window is fully opened
Maximum Sill Height
- Height from floor to sill: Maximum 1.5 meters (59 inches)
- Purpose: Ensures the window can be reached and climbed through in an emergency
Window Well Requirements (If Below Grade)
If your basement bedroom window is below grade (ground level), you need a window well that meets these requirements:
- Horizontal dimensions: Minimum 760 mm (30 inches) projection from the foundation wall
- Width: Must be at least the width of the window opening
- Drainage: Proper drainage to prevent water accumulation (typically gravel base)
- Ladder or steps: Required if window well is deeper than 600 mm (24 inches)
Common Egress Window Sizes
Most egress windows installed in Ontario basement bedrooms are:
- Casement windows: 24" × 48" or 30" × 48" (open fully to one side)
- Slider windows: 48" × 36" or 60" × 36" (half of the window opens)
- Awning windows: Less common for egress due to opening limitations
Casement windows are often preferred because they open fully, providing maximum unobstructed egress area.
Do Existing Windows Meet Code?
Many older basement windows don't meet current egress requirements. Standard basement windows (often 24" × 18" or smaller) don't provide enough opening area.
If you're converting an existing basement room into a bedroom, you'll need to install a code-compliant egress window. This typically involves:
- Cutting the foundation wall to enlarge the opening
- Installing a properly sized egress window
- Excavating and installing a window well (if below grade)
- Adding drainage (gravel or drain tile)
- Installing a window well cover (recommended for safety and weatherproofing)
Permits and Inspections
Installing an egress window in Ontario requires a building permit. The process involves:
- Submitting drawings showing window location, size, and window well dimensions
- Structural review (cutting into foundation wall)
- Inspection after installation
- Final approval before the bedroom can be legally used
Learn more about basement renovation permits in Ontario.
Safety and Fire Code
Beyond the egress window, basement bedrooms must also have:
- Working smoke alarm (hardwired and interconnected with upper floor alarms)
- Carbon monoxide alarm (if furnace or gas appliances are in basement)
- Minimum ceiling height of 1.95 m (6 feet 5 inches) for at least 75% of the room
Cost to Install an Egress Window
Egress window installation varies based on:
- Whether the window is below grade (requiring excavation and window well)
- Foundation wall material (poured concrete vs cinder block)
- Window size and type
- Interior finishing (drywall, trim)
Typical egress window installation includes cutting the foundation, installing the window, adding a window well, drainage, and interior finishing. Learn more about basement renovation costs.
Egress Windows in Hamilton Area Homes
We install egress windows for basement bedrooms throughout Hamilton, Dundas, Burlington, Ancaster, and Stoney Creek:
- Dundas: Older homes may have stone foundations requiring specialized cutting techniques
- Burlington: Post-war homes typically have poured concrete foundations
- Ancaster: Mix of heritage and modern homes with varying foundation types