The Ontario Building Code | Construction of Exposing Building Face and Walls above Exposing Building Face

9.10.14.5. Construction of Exposing building Face and walls above Exposing Building Face

(1) Except as provided in Sentences (2) to (7), each exposing building face and any exterior wall located above an exposing building face that encloses an attic or roof space shall be constructed in conformance with Table 9.10.14.5. and Subsection 9.10.8.

Table 9.10.14.5.
Minimum Construction Requirements for Exposing Building Faces

Forming Part of Sentences 9.10.14.5.(1) to (3)

Item	Column 1 Occupancy Classification of Building	Column 2 Maximum Area of Unprotected Openings Permitted, % of Exposing Building Face Area	Column 3 Minimum Required Fire-Resistance Rating	Column 4 Type of Construction Required	Column 5 Type of Cladding Required
1.	Residential, business and personal services, and low-hazard industrial	0 - 10	1 h	Noncombustible	Noncombustible
		>10 but ≤25	1 h	Combustible or noncombustible	Noncombustible
		>25 but <100	45 min	Combustible or noncombustible	Combustible or noncombustible
2.	Mercantile and medium-hazard industrial	0 - 10	2 h	Noncombustible	Noncombustible
		>10 but ≤25	2 h	Combustible or noncombustible	Noncombustible
		>25 but <100	1 h	Combustible or noncombustible	Combustible or noncombustible

(2) Cladding on exposing building faces and exterior walls located above exposing building faces need not conform to the type of cladding required by Table 9.10.14.5. where,

(a) the exposing building face is constructed with no unprotected openings,

(b) the limiting distance is not less than 0.6 m, and

(c) the cladding,

(i) conforms to Subsection 9.27.12.,

(ii) is installed without furring members over not less than 12.7 mm thick gypsum sheathing or over masonry,

(iii) has a flame-spread rating not more than 25 when tested in accordance with Sentence 3.1.12.1.(2), and

(iv) is not more than 2 mm in thickness exclusive of fasteners, joints and local reinforcements.

(3) Except as provided in Sentence (4), where a garage or accessory buildingserves a single dwelling unit and is detached from any building, the exposing building face,

Note: On July 1, 2017, Sentence 9.10.14.5.(3) of Division B of the Regulation is amended by striking out the portion before Clause (a) and substituting the following: (See: O. Reg. 139/17, s. 110 (1))

(3) Except as provided in Sentence (4), where a garage or accessory buildingserves a house or an individual dwelling unit in a house and is detached from the house and any other building, the exposing building face,

(a) need not conform to the minimum required fire-resistance rating in Table 9.10.14.5., where the limiting distance is 0.6 m or more,

(b) shall have a fire-resistance rating of not less than 45 min where the limiting distance is less than 0.6 m, and

(c) need not conform to the type of cladding required in Table 9.10.14.5. regardless of the limiting distance.

(4) The requirements for fire-resistance rating, type of construction and type of cladding need not apply to the exposing building faces of a dwelling unit and a detached garage or accessory building that face each other, where,

(a) the detached garage or accessory building serves a single dwelling unit,

(b) the detached garage or accessory building is located on the same property as that dwelling unit, and

(c) the dwelling unit served by the detached garage or accessory buildingis the only major occupancy on the property.

Note: On July 1, 2017, Sentence 9.10.14.5.(4) of Division B of the Regulation is revoked and the following substituted: (See: O. Reg. 139/17, s. 110 (2))

(4) The requirements for fire-resistance rating, type of construction and type of cladding need not apply to the exposing building facesof a house and a detached garage or accessory building that face each other, where,

(a) the detached garage or accessory building serves the house or an individual dwelling unit in the house,

(b) the detached garage or accessory building is located on the same property as the house, and

(c) the house is the only major occupancy on the property.

(5) Except for buildings containing 1 or 2 dwelling units only, combustible projections on the exterior of a wall that are more than 1 000 mm above ground level, such as balconies, platforms, canopies, eave projections and stairs, and that could expose an adjacent building to fire spread, shall not be permitted within,

Note: On July 1, 2017, Sentence 9.10.14.5.(5) of Division B of the Regulation is amended by striking out "Except for buildings containing 1 or 2 dwelling units only" in the portion before Clause (a) and substituting "Except for houses". (See: O. Reg. 139/17, s. 110 (3))

(a) 1.2 m of a property line or the centre line of a public way, or

(b) 2.4 m of a combustibleprojection on another building on the same property.

(6) Heavy timber and steel columns need not conform to the requirements of Sentence (1) provided the limiting distance is not less than 3 m.

(7) Non-loadbearing wall components need not have a minimum fire-resistance rating where,

(a) the buildingis 1 storey in building height,

(b) the building is of noncombustible construction,

(c) the buildingis classified as low hazard industrial occupancyand is used only for low fire load occupancies such as power generating plants or plants for the manufacture or storage of noncombustiblematerials, and

(d) the exposing building face has a limiting distance of 3 m or more.