What does the Building Code want on a garage wall in a Kanata home?

The answer depends on whether the garage is attached to the house and serves only that house. Where an attached garage serves only the home it is attached to, Ontario's Building Code treats it as part of that dwelling and says the fire separation "need not be provided" (9.10.9.18.(3)). We found no Type X or board-thickness requirement for that wall.

What the Code actually requires

What clause 9.10.9.18 requires is an air barrier system between the garage and the rest of the building, installed to block gas and exhaust fumes. The joints in that barrier must be sealed and structurally supported (9.10.9.18.(5)), and penetrations such as electrical boxes, wiring, piping and ductwork must also be sealed (9.25.3.3.(6)). Every door between the garage and the living space must be tight-fitting, weather-stripped and fitted with a self-closing device, and no such doorway may open into a sleeping room (9.10.13.15).

The Code also states, at clause 9.35.4.1.(1), that interior finish need not be applied to garage and carport walls. Many builders use taped and sealed drywall to form the gas barrier; what the Code requires is that the barrier is continuous and sealed, not that a particular board type is used.

These are minimums for new work; ask the City of Ottawa's Building Code Services how they apply to your renovation. Changing the door opening between the garage and the house may be permit work (the City's list includes enlarging or relocating a door), so ask before that kind of change.

A few things worth asking a contractor before work starts:

• Where are the existing penetrations in the garage-side wall or ceiling, and how will each one be sealed?
• Will the joints be taped and sealed, or is another membrane being used?
• Is the self-closing device on the door to the house in place and functioning?

The request form on this page sends your job details to Ottawa drywall contractors listed in the Ottawa Construction Network directory.