A Bit About Egress Windows

People who deal with the matter of egress windows know exactly what the key issues and questions are. Other people have never even heard the term before. The other day, I mentioned egress windows to a colleague and she thought that I was talking about a new invention to replace glass or plexiglass windows…

Simply put, egress means exit and whenever there’s any discussion about egress windows, it’s in reference to windows that are large enough to exit in a case of emergency, especially bedroom and basement windows.

As basement renovation and finishing have increased in popularity, building codes and product offerings have had to evolve in lock step. For example, some new product lines feature a large window with a large exterior window well and a step or steps to permit quick and easy evacuation. Be aware that if you are renovating your basement, part of the City of Ottawa’s permit and approval process involves indicating the size and location of doors and windows.

In any case, it’s all governed by Ontario’s Building Code. It requires that bedroom windows have a minimum total area of 3.8 square feet, and the openings (width or height) must be at least 15″. In the case of a basement window, the window well must be at least 24″ wide. The actual building code excerpt is as follows: 

Ontario Building Code (amended in 2012)

9.7.2.2. Other Requirements for Windows, Doors and Skylights

(1) Windows and skylights installed to provide required non-heating season ventilation shall conform to Article 9.32.2.1.

(2) Windows and doors installed to provide the required means of egress from bedrooms shall conform to Subsection 9.9.10.

9.9.10.1. Egress Windows or Doors for Bedrooms

(1) Except where a door on the same floor level as the bedroom provides direct access to the exterior, every floor level containing a bedroom in a suite shall be provided with at least one outside window that,

(a) is openable from the inside without the use of tools,

(b) provides an individual, unobstructed open portion having a minimum area of 0.35 m² with no dimension less than 380 mm, and

(c) maintains the required opening described in Clause (b) without the need for additional support.

(2) Except for basement areas, the window required in Sentence (1) shall have a maximum sill height of 1 000 mm above the floor.

(3) When sliding windows are used, the minimum dimension described in Sentence (1) shall apply to the openable portion of the window.

(4) Where the sleeping area within a live/work unit is on a mezzanine with no obstructions more than 1 070 mm above the floor, the window required in Sentence (1) may be provided on the main level of the live/work unit provided the mezzanine is not more than 25% of the area of the live/work unit or 20 m2, whichever is less, and an unobstructed direct path of travel is provided from the mezzanine to this window.

(5) Where a window required in Sentence (1) opens into a window well, a clearance of not less than 550 mm shall be provided in front of the window.

(6) Where the sash of a window referred to in Sentence (5) swings towards the window well, the operation of the sash shall not reduce the clearance in a manner that would restrict escape in an emergency.

(7) Where a protective enclosure is installed over the window well referred to in Sentence (5), such enclosure shall be openable from the inside without the use of keys, tools or special knowledge of the opening mechanism.
It is further recommended that the best window type is a double-slider because it’s easy to open.

If in doubt about whether your existing bedroom windows meet the safety requirements set out in the Code or if you’re about to undertake a basement refurbishment that will involve the windows, it’s always best to contact our municipal authorities.

So, let there be light! (& safe egress!)