Egress Windows: What Calgary Code Requires and Why

An egress window is a window large enough for someone to escape through in an emergency — and for a firefighter to enter — and Calgary code requires one in every basement bedroom and in any legal secondary suite. It's a life-safety requirement, not a design choice. Here's exactly what the code asks for, why it matters, and what adding one to a Calgary basement typically costs.

What "egress" means and why it's required

"Egress" simply means a way out. In a basement, the stairs are one exit — but in a fire, smoke and flames can block the stairwell, leaving anyone in a bedroom trapped. An egress window provides a second, independent escape route directly to the outside, and it doubles as the way emergency responders get in. That's why the building code requires a proper egress window for any room used for sleeping below grade. Skip it, and the bedroom (or suite) isn't legal — and far more importantly, it isn't safe.

What Calgary code requires for an egress window

Calgary follows the Alberta Building Code, which sets clear minimums for an egress (escape) window serving a bedroom. The key requirements:

• Minimum unobstructed opening of roughly 0.35 m² (about 3.8 sq ft) of clear, openable area — the actual gap a body can pass through once the window is open, not the size of the glass.
• No dimension less than about 380 mm (15 inches) — so the opening can't be a long, thin slot that no one could fit through.
• A reachable sill height — the bottom of the opening must be low enough above the floor to climb out without a step or ladder.
• A window well that maintains clearance where the window sits below grade, so the opening isn't blocked by soil and a person can climb up and out. If a well is deep, a ladder or step may be required.
• It must open from the inside without tools, keys, or special knowledge.

Because the clear opening is what counts — not the rough window size — getting an egress window right is a job for someone who builds them to code regularly. As part of a full basement development, we handle the foundation cut, the window, the well, the permit, and the inspection together — egress is built into the larger project, not something we install on its own. (Always confirm exact current requirements through the permit; codes are updated periodically.)

Why most basements need foundation work to add one

Existing basement windows are usually too small to meet egress requirements. Making one compliant typically means cutting the concrete foundation to enlarge the opening, installing the larger egress window, and adding a window well outside so the window clears the surrounding ground. It's structural work — done properly, with the right lintel and waterproofing — which is why it's not a DIY swap and why it's priced as its own line item in a basement quote.

What does an egress window cost in Calgary?

As a guide, expect the egress window (supply + the foundation opening) to run around $3,400, plus about $1,210 for the window well. So a typical egress window with its well lands in the neighbourhood of $4,600, before any landscaping to finish around it. (These are typical guide prices from our current Calgary cost catalogue — your exact cost is confirmed in a fixed-price quote, since it depends on the foundation, depth, and well size.)

When you need an egress window

You need a code-compliant egress window if your basement plans include:

• A bedroom — any below-grade sleeping room requires one.
• A legal secondary suite — egress is one of the core legal-suite requirements, alongside permits, fire separation, and independent systems.
• A future bedroom or suite — if there's any chance you'll add one later, roughing the opening in during the build is far cheaper than cutting a finished, furnished basement apart afterward.

A finished basement rec room generally doesn't require egress — but the moment you call a room a bedroom, the requirement kicks in.

Frequently asked questions