buildings that contain only dwelling units and have no dwelling unit above another dwelling unit, and
houses with a secondary suite including their common spaces. (See Note A-9.10.15.1.(1).)
9.10.15.2.
Area and Location of Exposing Building Face
The area of an exposing building face shall be
taken as the exterior wall area facing in one direction on any side of a building, and
calculated as
the total area measured from the finished ground level to the uppermost ceiling,
the area for each fire compartment, where a building is divided into fire compartments by fire separations with fire-resistance ratings not less than 45 min, or
except as provided in Sentence (2), where Table 9.10.15.4. is used to determine the maximum aggregate area of glazed openings, the area of any number of individual vertical portions of the wall measured from the finished ground level to the uppermost ceiling. (See Note A-9.10.15.4.(2).)
Where the exposing building face of any section of an exterior wall enclosing a single room or space, or combination room and space, has a limiting distance of 2 m or less, that section of the exposing building face serving the room or space shall not be divided into portions for the purpose of calculating area of exposing building face. (See Sentence 9.10.15.4.(5) and Note A-9.10.15.4.(2).)
For the purpose of using Table 9.10.15.4. to determine the maximum permitted area of glazed openings in an irregularly shaped or skewed exterior wall, the location of the exposing building face shall be taken as a vertical plane located so that there are no glazed openings between the vertical plane and the line to which the limiting distance is measured. (See Note A-3.2.3.1.(4).)
In determining the required cladding-sheathing assembly and fire-resistance rating for an irregularly shaped or skewed exterior wall, the location of the exposing building face shall be taken as a vertical plane located so that no portion of the actual exposing building face is between the vertical plane and the line to which the limiting distance is measured. (See Article 9.10.15.5. and Note A-3.2.3.1.(4).)
9.10.15.3.
Limiting Distance and Fire Department Response
Except for the purpose of applying Sentences 9.10.15.2.(2), 9.10.15.4.(3) and 9.10.15.5.(13), a limiting distance equal to half the actual limiting distance shall be used as input to the requirements of this Subsection, where
the time from receipt of notification of a fire by the fire department until the first fire department vehicle arrives at the building exceeds 10 min in 10% or more of all calls to the building, and
any storey in the building is not sprinklered. (See Notes A-3.2.3. and A-3.2.3.1.(8).)
9.10.15.4.
Glazed Openings in Exposing Building Face
Except as provided in Sentence (6), the maximum aggregate area of glazed openings in an exposing building face shall
conform to Table 9.10.15.4.,
conform to Subsection 3.2.3., or
where the limiting distance is not less than 1.2 m, be equal to or less than the limiting distance squared.
Where the limits on the area of glazed openings are determined for individual portions of the exterior wall, as described in Subclause 9.10.15.2.(1)(b)(iii), the maximum aggregate area of glazed openings for any portion shall conform to the values in the row of Table 9.10.15.4. corresponding to the maximum total area of exposing building face (see column 1 of the Table) that is equal to the sum of all portions of the exposing building face. (See Note A-9.10.15.4.(2).)
Except for buildings that are sprinklered and for openable windows having an unobstructed opening equal to 0.35 m2 installed in accordance with Sentences 9.9.10.1.(1) and (2), where the limiting distance is 2 m or less, individual glazed openings or a group of glazed openings in an exposing building face shall not exceed 50% of the maximum allowable aggregate area of glazed openings determined in Sentence (1).
The spacing between individual glazed openings described in Sentence (3) serving a single room or space described in Sentence (5) shall be not less than
2 m horizontally of another glazed opening that is on the same exposing building face and serves the single room or space, or
2 m vertically of another glazed opening that serves the single room or space, or another room or space on the same storey.
For the purpose of Sentence (4), "single room or space" shall mean
two or more adjacent spaces having a full-height separating wall extending less than 1.5 m from the interior face of the exterior wall, or
two or more stacked spaces that are on the same storey.
The limits on the area of glazed openings shall not apply to the exposing building face of a dwelling unit facing a detached garage or accessory building, where
the detached garage or accessory building serves only one dwelling unit,
the detached garage or accessory building is located on the same property as that dwelling unit, and
the dwelling unit served by the detached garage or accessory building is the only major occupancy on the property.
Table 9.10.15.4.
Maximum Area of Glazed Openings in Exterior Walls of Houses
Forming Part of Sentences 9.10.15.4.(1) and (2)
9.10.15.5.
Construction of Exposing Building Face of Houses
Except as provided in Sentences (4) and (13), 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 Sentences (2) and (3)
for the exposing building face as a whole, or
for any number of separate portions of the exposing building face (see Subclause 9.10.15.2.(1)(b)(iii), Sentence 9.10.15.4.(2), and Note A-9.10.15.4.(2)). (See also Subsection 9.10.8.)
Except as provided in Sentences (4) and (5), where the limiting distance is less than 0.6 m, the exposing building face and exterior walls located above the exposing building face that enclose an attic or roof space shall have a fire-resistance rating of not less than 45 min, and
be installed without furring members over gypsum sheathing at least 12.7 mm thick or over masonry,
have a flame-spread rating not greater than 25 when tested in accordance with Sentence 3.1.12.1.(2), and
not exceed 2 mm in thickness exclusive of fasteners, joints and local reinforcements, or
the wall assembly shall comply with Clause 3.1.5.5.(1)(b) when tested in conformance with CAN/ULC-S134, "Fire Test of Exterior Wall Assemblies."
Except as provided in Sentence (4), where the limiting distance is equal to or greater than 0.6 m and less than 1.2 m, the exposing building face and any exterior wall located above the exposing building face that encloses an attic or roof space shall have a fire-resistance rating of not less than 45 min, and
be installed without furring members, or on furring not more than 25 mm thick, over gypsum sheathing at least 12.7 mm thick or over masonry, and
after conditioning in conformance with ASTM D 2898, "Accelerated Weathering of Fire-Retardant-Treated Wood for Fire Testing," have a flame-spread rating not greater than 25 when tested in accordance with Sentence 3.1.12.1.(2),
be installed with or without furring members over gypsum sheathing at least 12.7 mm thick or over masonry,
have a flame-spread rating not greater than 25 when tested in accordance with Sentence 3.1.12.1.(2), and
not exceed 2 mm in thickness exclusive of fasteners, joints and local reinforcements, or
the wall assembly shall comply with Clause 3.1.5.5.(1)(b) when tested in conformance with CAN/ULC-S134, "Fire Test of Exterior Wall Assemblies."
The requirements regarding fire-resistance rating and type of cladding-sheathing assembly shall not apply to the exposing building face or projections from an exposing building face of a dwelling unit facing a detached garage or accessory building, or a garage or accessory building facing a dwelling unit, where
the detached garage or accessory building serves only one dwelling unit,
the detached garage or accessory building is located on the same property as that dwelling unit, and
the dwelling unit served by the detached garage or accessory building is the only major occupancy on the property.
Except as provided in Sentence (6), combustible projections on the exterior of a wall that are more than 1 m above ground level and that could expose an adjacent building to fire spread shall not be permitted within
1.2 m of a property line or the centre line of a public way, or
2.4 m of a combustible projection on another building on the same property.
Except as provided in Sentences (8) to (11), Sentence (5) shall not apply to
buildings containing 1 or 2 dwelling units only, and
detached garages or accessory buildings, where
the detached garage or accessory building serves only one dwelling unit,
the detached garage or accessory building is located on the same property as that dwelling unit, and
the dwelling unit served by the detached garage or accessory building is the only major occupancy on the property. (See Note A-9.10.14.5.(7).)
Where combustible projections on an exposing building face are permitted by Sentence (6), are totally enclosed and constructed with solid faces, such as for fireplaces and chimneys, and extend within 1.2 m of a property line,
the construction of the face and sides of the projection shall comply with the corresponding requirements for exposing building faces for limiting distances less than 1.2 m as stated in Sentence (2) or (3), and
where the underside of the projection is more than 0.6 m above finished ground level, it shall be protected by
not less than 0.38 mm thick noncombustible material,
unvented aluminum conforming to CAN/CGSB-93.2-M, "Prefinished Aluminum Siding, Soffits, and Fascia, for Residential Use,"
not less than 12.7 mm thick gypsum soffit board or gypsum ceiling board installed according to CSA A82.31-M, "Gypsum Board Application,"
Except as provided in Sentence (10), where the exposing building face has a limiting distance of not more than 0.45 m, projecting roof soffits shall not be constructed above the exposing building face. (See Note A-3.2.3.6.(2).)
Except as provided in Sentence (10), where the exposing building face has a limiting distance of more than 0.45 m, the face of roof soffits shall not project to less than 0.45 m from the property line. (See Note A-3.2.3.6.(2).)
The face of a roof soffit is permitted to project to the property line, where it faces a street, lane or public thoroughfare. (See Note A-9.10.14.5.(11) and 9.10.15.5.(10).)
Where roof soffits project to less than 1.2 m from the property line, the centre line of a lane or public thoroughfare, or an imaginary line between two buildings or fire compartments on the same property, they shall
have no openings, and
be protected by
not less than 0.38 mm thick sheet steel,
unvented aluminum conforming to CAN/CGSB-93.2-M, "Prefinished Aluminum Siding, Soffits, and Fascia, for Residential Use,"
not less than 12.7 mm thick gypsum soffit board or gypsum ceiling board installed according to CSA A82.31-M, "Gypsum Board Application,"
not less than 11 mm thick plywood,
not less than 12.5 mm thick OSB or waferboard, or
not less than 11 mm thick lumber. (See Note A-3.2.3.6.(2).)
For buildings of combustible construction, materials installed to provide the required protection for soffits may be covered with a combustible or noncombustible finish material.
Heavy timber and steel columns need not conform to the requirements of Sentence (1), provided the limiting distance is not less than 3 m.
