Egress Window is a term that describes not just a window type but a set of procedures that need to be performed in order to get your basement qualified for fire safety standards of the Ontario Building code.

Egress window is a key feature ensuring you and your family enjoying your basement space with the most comfort and safety. This essential addition to your basement lets plenty of natural light in and what even more important is compliant with the fire safety regulations, fulfilling an extra exit requirement in case of an emergency.

Egress Window build and installation is a complex process requiring cutting through the foundation wall. Concreate is the hardest structural material when it comes to providing upgrades requiring special craftmanship skill as well as heavy duty commercial equipment.

The proper outside finish of the Egress Window just as important as the window itself. All the egress projects require window well with a sufficient drainage system providing solid flood prevention. The digging will go all the way down to the footing of the foundation wall where drainage pipe will be installed from the bottom of the window to the weeping tile.

Prior to window well digging Locate Service involvement ensures no communications such as gas line, telecommunication cables, water supply, etc. are located along the affected area.

Egress window width, length and projection should be correctly sized to ensure code compliance.


Emergency Requirements for Egress Windows

National Building Code of Canada

  1. Light (at least five per cent of the floor area served)

  2. Ventilation (at least 0.28m² or 3 ft² or an adequate year-round mechanical ventilation)

  3. Emergency Escape: An Emergency Escape requires that each bedroom must have a door that leads directly to the exterior of the building or have a properly-sized egress window that can be opened from the inside without the use of keys, tools, hardware or special knowledge (unless this bedroom has a sprinkler system installed).

Building Code article establishes the general requirement that all bedrooms must have at least one window that is large enough to be used as an exit in an emergency. The specific requirements are as follows:

Except where the suite has a sprinkler, each bedroom or combination bedroom shall have at least one outside window or exterior door operable from the inside without the use of key, tools or special knowledge and without the removal of sashes or hardware.

The window referred to in Sentence (1) shall provide and unobstructed opening of not less than 0.35 m² (542 in² or 3.8 ft²) in area with no dimension less than 380 mm (15 inches), and maintain the required opening during an emergency without the need for additional support.

If the window referred to in Sentence (1) is provided with security bars, the security bars shall be operable from the inside without the use of any tools or special knowledge.

If a window well is required, it must be out from the window at least 550mm (about 22″) to provide safe passage. Awning style windows for example opening into a window well typically won’t work because they tend to obstruct clear passage unless the window well is unusually large.

Ontario Building Code


Egress from Bedrooms (OBC 9.9.10 – 2012)
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,

    1. is openable from the inside without the use of tools,

    2. provides an individual, unobstructed open portion having a minimum area of 0.35 m² (3.8 ft²) with no dimension less than 380 mm (15 inches), and

    3. 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 (39 inches) 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 (22 inches) 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.

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.

Fire Code Requirements for Rental Units in basement

Two exits are required. Once exit can be through the stairs to the first floor, the second exit can be through another door or a properly sized window.