The Ontario Building Code | Group D, up to 6 Storeys, Sprinklered, Combustible Construction
3.2.2.50A. Group D, up to 6 Storeys, Sprinklered, Combustible Construction
(1) A building classified as Group D is permitted to conform to Sentence (2) provided,
(a) it is sprinklered,
(b) it is not more than 6 storeys in building height,
(c) it has a height of not more than 18 m, measured between the floor level of the first storeyand the floor level of the uppermost storey or mezzanine that is not a rooftop enclosure provided for elevator machinery, a stairway or a service room used for no purpose other than for service to the building, and
(d) it has a building area of not more than,
(i) 18 000 m2if 1 storey in building height,
(ii) 9 000 m2if 2 storeys in building height,
(iii) 6 000 m2if 3 storeys in building height,
(iv) 4 500 m2if 4 storeys in building height,
(v) 3 600 m2if 5 storeys in building height, or
(vi) 3 000 m2if 6 storeys in building height.
(2) The building referred to in Sentence (1) is permitted to be of combustible construction or noncombustible construction used singly or in combination, and,
(a) floor assemblies shall be fire separations with a fire-resistance rating not less than 1 h,
(b) roof assemblies shall have a fire-resistance rating not less than 1 h,
(c) except as provided by Sentence (3), where the roof assembly has a height greater than 25 m measured from the floor level of the first storey to the highest point of the roof assembly, the roof assembly shall,
(i) be of noncombustible construction, or
(ii) be constructed of fire-retardant treated wood conforming to Article 3.1.4.5.,
(d) mezzaninesshall have a fire-resistance rating not less than 1 h,
(e) the fire separation of exits described in Sentence 3.4.4.1.(3) shall be of noncombustible construction, and
(f) loadbearingwalls, columns and arches shall have a fire-resistance rating not less than that required for the supported assembly.
(3) The construction of non-contiguous roof assemblies at different elevations is permitted to be evaluated separately to determine which roof assemblies are required to be constructed in accordance with Clause (2)(c).
(4) Group A, Division 2 major occupancies, Group E major occupancies and storage garages located in a building within the scope of this Article are permitted to be constructed in accordance with this Article provided they are located below the third storeyof the building.