Window replacement permits and bedroom egress rules in Canada

01 /Do you need a permit to replace windows?

Usually not, if you are replacing like with like in a house, but it depends on your municipality and on exactly what changes. Building permits in Canada are issued locally under the building code adopted by each province or territory, so the only reliable answer comes from your municipality's building department. The general pattern across Canadian cities looks like this.

02 /What do Calgary and Toronto say?

Two large cities publish clear guidance, and they show how rules can differ in the details. Both were checked on the cities' own websites in September 2026.

• Calgary. The City's home renovations page says that if you are replacing windows without changing the size of the opening or the type or operation of the window, no permit is required; if you are adding new windows or enlarging existing ones, a building permit is required. It adds that a window in a bedroom must meet the egress requirements of the National Building Code (Alberta Edition), and that a professional engineer's structural review is required when a new opening in a concrete foundation wall is wider than 1.2 m (4 ft), among other triggers.
• Toronto. The City's permit page says replacing a window or door in an existing opening in a detached, semi-detached or row house containing a single dwelling unit does not need a building permit, provided the opening's location and size do not change, the structural support is not altered or affected, and no new exit is created. Replacing windows or doors in other buildings does need a permit, and compliance with the zoning bylaw is required even when a permit is not.

Edmonton's renovations page, checked in September 2026, lists replacing windows of the same size among projects that do not need a permit, and requires one for adding a window or changing its size; window replacement in Alberta sets the two Alberta cities side by side. Other municipalities may follow either pattern or their own. If your house is a duplex, has a secondary suite, or is part of a condominium, assume you need to ask. Your installer should know local practice, but the owner is usually responsible for making sure permits are in place, so confirm in writing who will apply.

03 /What are the egress rules for bedroom windows?

Building codes require bedrooms to have a way to escape in an emergency, which usually means a window large enough to climb through. NRCan's retrofit guide reminds homeowners that codes require every bedroom to have at least one window that opens from the inside for escape, and to keep that in mind before sealing any window shut.

The Alberta Safety Codes Council's bedroom window tip sheet, written for the National Building Code 2019 Alberta Edition, describes the requirement this way: unless a bedroom has an exterior door or the building is sprinklered, at least one window must open from the inside without tools or special knowledge and provide an unobstructed opening of at least 0.35 m² (3.77 ft²) with no dimension less than 380 mm (15 in.). The opening must be achieved without removing sashes or hardware, and the window must stay open without being held. The City of Ottawa's 2025 advisory under the Ontario Building Code lists the same area and dimension.

04 /Can a replacement window make a bedroom non-compliant?

Yes. The most common way is an insert. Because the new window sits inside the old frame, the clear opening shrinks on every side, and a bedroom window that barely met the minimum before may fail it afterwards. Changing the operation can do it too: a casement that opened fully may be replaced by a slider that opens only half its width.

• Measure the existing clear opening of each bedroom window before you choose a product or method.
• Ask the supplier for the clear opening dimensions of the proposed window in its fully open position.
• For casements, ask about hinges that let the sash open to a full, clear position.
• If a window has an opening limiter for child safety, it must be releasable for escape; Ottawa's advisory, for example, requires limiters on low-sill egress windows to be bypassable without tools.
• Where the numbers are tight, choose full-frame replacement or a different operating type.

05 /What about enlarging a basement window?

Enlarging a basement window, usually to create a legal bedroom, is construction rather than replacement. It means cutting the foundation wall, adding a header or lintel as designed, installing a larger window and building a window well large enough for escape. Expect a building permit, and in some cases engineering.

Calgary's guidance, for example, requires a building permit to add or enlarge windows, an engineer's structural review when a new foundation opening is wider than 1.2 m, and notes that a window well can project a maximum of 0.8 m into a side setback. Rules differ elsewhere, so start with your municipality. The Alberta tip sheet also advises talking to the municipality's development and safety codes officers before renovating to add or upgrade bedroom windows.

06 /What other approvals might apply?

• Condominiums: windows are often part of the common elements or the building envelope. Check your declaration and bylaws and get the board's written approval before ordering, including approved colours and profiles.
• Heritage properties: designated buildings and heritage districts may require approval for any exterior change, including window material, profile and muntin pattern.
• Zoning: projecting windows, such as bays, and window wells can be limited by setback rules.
• Upper-floor windows: codes regulate guards or opening limiters for windows with low sills high above the ground; a replacement with a different sill height or operation can change what is required.

None of this is legal advice. Treat the city examples on this page as illustrations of the pattern, and confirm your own case with the municipality. The window types guide helps you choose an operation that suits egress, and the Window Quote Checker flags quotes that do not state the installation method. When you request quotes, mention which windows serve bedrooms.

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