What is the minimum size for a basement bedroom window to qualify as egress?

In Ottawa, a basement bedroom window must have a minimum opening area of 3.77 square feet (0.35 m²) to qualify as egress, with no dimension less than 15 inches (380mm) wide. However, the sill height cannot exceed 3.6 feet (1.1m) from the floor, which is often the bigger challenge in basement bedrooms.

The Ontario Building Code (OBC) sets strict egress requirements for basement bedrooms because they're considered sleeping areas that need emergency escape routes. Beyond the window size, you also need adequate window well dimensions - the well must extend at least 24 inches (600mm) from the window and be at least as wide as the window opening. The well also requires proper drainage and often a ladder or steps if it's deeper than 24 inches.

Most standard basement windows don't meet egress requirements, which is why many Ottawa homeowners need to install larger egress windows when finishing basements or creating secondary suites. This typically involves cutting through the foundation wall, installing a larger window buck, and excavating for a proper window well. The process requires careful waterproofing and proper grading to prevent water infiltration.

In Ottawa's clay soil conditions, egress window installation requires extra attention to drainage and waterproofing. The frost line depth of 4 feet means the window well needs proper insulation and drainage systems that won't freeze. Most installations also require a building permit from the City of Ottawa, especially when you're enlarging the opening or adding a bedroom to the basement.

Professional installation is strongly recommended for egress windows because improper waterproofing can lead to serious basement flooding issues. The work involves structural modifications to your foundation, electrical work for proper lighting in the well, and coordination with drainage systems. A typical egress window installation in Ottawa runs $3,000 to $6,000 depending on the complexity of excavation and existing foundation conditions.

If you're planning a basement bedroom or secondary suite, the egress window is often one of the first requirements to address. The City of Ottawa requires these windows for any basement sleeping area, and they're essential for both safety and legal compliance. For a free assessment of your basement's egress window needs, contact Ottawa Basements - we can evaluate your specific situation and ensure your project meets all OBC requirements.

---

Find a Licensed Contractor

Ottawa Basements connects you with vetted, licensed renovation contractors from the Ottawa Construction Network:

• Renovo Construction ✓
• Bartosh Construction Inc ✓
• Justyn Rook Contracting ✓