The mortgage helper, mother-in-law suite, guest-apartment, bachelor pad, whatever it may be called, having a secondary suite in Victoria’s single-family residences has become commonplace with homeowners for a variety of economic and lifestyle reasons. Building a secondary suite, whether by remodeling or in new construction, comes with many responsibilities led by regulations that draw a lot of questions, so many, that Alair Homes Victoria has created a series article on building a Legal and Code-Compliant secondary suite in greater Victoria, starting with this month’s introduction to Fire Separations.

Purpose of Fire Separtions

A Fire Separation is a barrier that prevents the spread of fire from one building compartment area to another. For secondary suites, the BC Building Code requires a 45 or 60 minute Fire Separation between the main suite and secondary suite (whether it’s deemed a 45 or 60 minute rating depends on the number of stories and positioning of the suites within). A 45 minute time rating means that the separating wall or floor/ceiling assembly can withstand fire passage for 45 minutes when tested to the Canadian National Standard CAN/ULC S101.

The Four Parts of Fire Seperations

There are four parts of the Fire Separation construction to consider: Walls, Floor/Ceiling, Doorways, and Penetrations, which are all treated differently by the Code as to how to evaluate fire resistance. Each part has to be built in accordance with the guidelines of the Code to achieve the necessary rating. The Code allows for three methods of demonstrating compliance:

  1. Prescribed construction assembly details of walls, floor/ceilings, and doorways, as well as product specifications for penetration seals and fire blocking, in exact accordance with the Code
  2. Engineering Evaluation, as there are many additional acceptable construction details and products in the marketplace that the Code provides guidance as to how approved laboratories can perform tests that demonstrate compliance of the fire-resistance rating
  3. Design with materials of known fire-resistance configured together, adding each component’s individual contribution to the sum total by stacking layers until the minutes add up to 45 (or 60)

Achieving Safety & Aesthetic

fire-seperations

Owners and builders have many options when building a Fire Separation for a secondary suite, a good thing for the experienced and educated practitioners who can use the multitude of solutions to fit their budget and aesthetic tastes while achieving safety and protection.

As the article series continues, Alair Homes Victoria will show examples and Code references as to how to specify, plan check, build, and inspect Fire Separation assemblies. Next month we will further explore how to construct a 45 or 60 minute Fire Separation Wall.