Basement Egress Windows in Toronto & the GTA

Under the Ontario Building Code, an egress window must have an unobstructed opening of at least 0.35 m² (about 3.8 sq ft) with no dimension less than 380 mm (15 in). It must open from the inside without tools or special knowledge and stay open on its own. A 380 mm by 380 mm opening is not enough on its own, because it does not reach the 0.35 m² area.

The Ontario Building Code requires at least one egress window or exterior door on each floor level that contains a bedroom, unless the suite is sprinklered. How that applies to your basement depends on the layout, and it is checked at the permit stage, so we confirm the requirement for your rooms during design.

Where an egress window opens into a window well, the Ontario Building Code requires at least 550 mm of clear space in front of the window, and a window that swings into the well must not reduce that space. A deep well needs a safe way to climb out, so wells more than about 1 m deep usually need built-in steps or a ladder. The well also needs drainage so it does not fill with water.

For a bedroom egress window, the sill should be no more than 1,000 mm (about 3 ft 3 in) above the finished floor, so a person can climb out in an emergency.

Usually yes. Cutting into a foundation wall to enlarge an opening or make a new one changes the structure, so it generally needs a building permit and an engineered lintel. Replacing a window in an existing opening without cutting the foundation usually does not. We prepare the drawings and handle the application.

In most cases, yes. We cut the foundation below the existing opening, install a lintel sized for the new opening, fit a code-compliant window, and excavate and build a drained window well outside. If the wall cannot be cut where the bedroom is, we look at other options, such as moving the bedroom or adding a separate entrance.