Notice: This site currently shows the 2012/2017 edition of the Ontario Building Code. The current legally effective code is the 2024 edition (O.Reg. 163/24), in effect since January 1, 2025. Confirm current requirements at ontario.ca.

The Ontario Building Code | Fire Dampers

9.10.13.13. Fire Dampers

(1) Except as permitted in Sentences (2) to (5) and Sentence 9.10.5.1.(4), a duct that penetrates an assembly required to be a fire separationwith a fire-resistance rating shall be equipped with a fire damper in conformance with Articles 3.1.8.4. and 3.1.8.9.

(2) Afire damper is not required where a noncombustible branch duct pierces a required fire separation provided the duct,

(a) has a melting point not below 760°C,

(b) has a cross-sectional area less than 130 cm², and

(c) supplies only air-conditioning units or combined air-conditioningand heating units discharging air at not more than 1.2 m above the floor.

(3) Afire damper is not required where a noncombustible branch duct pierces a required fire separation around an exhaust duct riser in which the air flow is upward provided,

(a) the melting point of the branch duct is not below 760°C,

(b) the branch duct is carried up inside the riser at least 500 mm, and

(c) the exhaust duct is under negative pressure as described in Article 9.10.9.18.

(4) Noncombustible ducts that penetrate a fire separation separating a vertical service space from the remainder of the buildingneed not be equipped with a fire damper at the fire separation provided,

(a) the ducts have a melting point above 760°C, and

(b) each individual duct exhausts directly to the outside at the top of the vertical service space.

(5) A duct serving commercial cooking equipment and piercing a required fire separation need not be equipped with a fire damper at the fire separation.

In Plain Language

Fire dampers, mechanical devices that close off a duct during a fire, are required at locations set out in this article, preventing ductwork from becoming a path for fire spread.

This is a plain-language summary of the 2012/2017 Ontario Building Code text above, for general understanding only and not a substitute for the Code. Always confirm current requirements against the 2024 edition (O.Reg. 163/24) or a qualified professional before construction.