Basement Windows and the EGRESS Building Code

Every year I get several calls from people wanting to make their basement windows larger. Sometimes it’s because they need to meet the specifications of the EGRESS code and sometimes it’s just for more light and or ventilation and it often involves cutting concrete.

Many cities, including Edmonton require a building permit before enlarging the size of an existing window or adding a new one. It is up to the homeowner to acquire a building permit but some contractors will apply on your behalf for a fee. There are three documents that are required when applying for a building permit for exterior renovations on your home which includes changing the size of an existing window or door or adding new ones:

  1. Site Plan which must include your address, an arrow indicating where north is, corresponding streets and avenues, dimensions of property lines location, measurements, and setbacks of proposed and existing buildings and structures and identify applicable caveats, covenants, easements.
  2. Elevation Drawings showing proposed alterations or additions of windows and doors, and their dimensions.
  3. A Window Location Plan if your property is located in the Mature Neighbourhood Overlay and your project includes adding or changing a window in a side yard, a window location plan is required.

For more information visit the City of Edmonton’s web site:

There are many considerations to think about before you go ahead with adding or increasing the size of your basement window. 


The picture of this basement window is fairly typical for an Edmonton home built in the 60’s. The bottom of the window was only a few inches above grade so if the customer were to increase the height of the window, a window well would have to be installed to keep back the earth from around the window.

A window well is designed to move any standing water down into the weeping tile located at the bottom of your foundation as indicted by the diagram to the left.

If the window needs to meet the EGRESS code, the size of the window well  must project out at least 760 mm (about 30″) giving enough space to easily get out.

This basement window was being increased in both width and height and although it was not going to end up below grade it was necessary to dig down in order to make room for the concrete saw.

The lines drawn on the wall indicate the size of the new rough opening.

Most professional concrete cutting companies use a saw that has a rail which is attached to the wall giving you a straight even cut. 

A wood buck is often installed into the rough opening onto the concrete making installing a window much easier.

The saw and the rail are anchored to the wall. Electrical power and water are hooked up and the cut proceeds.

Concrete saws use water for lubrication and cooling which can cause quite a mess on the inside.

The water from the concrete blade can make quite the mess and if the room that your working in is finished you’ll want to horde off the cut area minimizing any clean up that will occur.

If the new window size is increasing in width and if your floor joist terminate above the cut area you may need a header or lintel to insure proper support. 

The 2014 Alberta Building Code (ABC 2014) states the following for bedroom windows and window wells: Egress Windows or Doors for Bedrooms:

  1. Except where the suite is sprinklered, each bedroom or combination bedroom shall have at least one outside window or exterior door openable from the inside without the use of key, tools or special knowledge and without the removal of sashes or hardware.
  2. The window referred to in Sentence (1) shall a)provide and unobstructed opening of not less than 0.35 m2 in area with nodimension less than 380 mm, and b)maintain the required opening during an emergency without the need for additional support.
  3. If the window referred to in Sentence (1) is provided with security bars, the security bars shall be openable from the inside without the use of any tools or special knowledge.
  4. Where a window required in Sentence (1) opens into a window-well, a clearance of not less than 760 mm shall be provided in front of the window.
  5. Where the sash of a window referred to in Sentence (3) 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.
  6. Where a protective enclosure is installed over the window well referred to in Sentence(3), the enclosure shall be openable from the inside without the use of keys, tools or special knowledge of the opening mechanism. .