Egress, Ingress, and the BC Building Code

Have you ever heard the terms egress or ingress in relation to windows and wondered what they mean? Or have an upcoming project and wondering how the requirements of the BC Building Code will affect it? You’ll want to read the latest installment of the Window Geeks: Master Class!

What is egress?

At its most basic, egress is the action of leaving a place. When it comes to egress windows, they are designed to allow for a quick and safe exit from a home in case of an emergency such as a fire.

What is ingress?

Ingress is essentially the opposite of egress. Ingress relates to an entryway that allows a first responder to enter a building during an emergency.

What are the egress requirements of the BC Building Code?

For unsprinklered buildings, the building code requires bedrooms to have 2 paths of egress: one through the room door, and one by another means. This will typically be a window or patio door. Buildings with sprinkler systems do not require bedroom egress.

In the 2018 version of the BC Building Code, part 9: housing and small buildings describes the exit requirements of a building in the event of a fire. The building should be designed according to the guidelines provided in this section to maintain safe standards that will preserve human life. Section 9.9 of the code goes into detail with the types and purposes of exits and how they should be designed in order for the building to be compliant. It also references the closely associated section 9.10 for fire protection of said egress exits.

Although sub-section 9.9.2.3 says that windows are not considered a required means of egress, 9.9.9 (egress from dwelling units) and 9.9.10 (egress from bedrooms) describe the specifications for a window to be used as an egress exit in case of a fire.

We can look at a three-floor townhome to demonstrate the requirements of Section 9.9.9. If the townhome has a top-level window and no balcony, someone trying to escape would be required to travel more than one floor to exit the building. The window size may not be less than 1 metre (approx. 40”) in height by 0.55 meters (approx. 21.75”) in width. The sill of the window must also be not less than 1 metre above the floor and 7 metres from the ground level.

How is this requirement actually enforced?

The egress requirements for a part 9 building would be enforced by the building inspector acting on behalf of the city the project is built in. If the specifications for the project indicate notes for egress requirements, the architect and the contractor/developer can enforce this.

Egress requirements are contradicted when a 100 mm (4”) restricting device is required to limit the free-swinging or sliding action of a window to prevent fall hazards, especially for small children. Based on upcoming code, windows with a sill height below 36” in part 9 buildings will require restrictors (the current code, which will be obsolete as of March 2023, has this as 18”). With the travel limit requirement for windows at the top level of a three-floor part 9 building, if there is no exit from the 2^nd storey nor a balcony on the 3^rd, to fulfill 9.9.9.1. of the code you must have a window of the correct size with a sill height between 36” and 39”.