On January 1, 2015, new Ontario Building Code (OBC) amendments became effective that increase the permitted height of residential (Group C) and office buildings (Group D) wood-frame buildings from four to six storeys. These buildings will feature several additional safety provisions not currently required in four-storey wood buildings, including: enhanced automatic sprinklering to the NFPA 13 standard; sprinklering of all balconies over 610 mm deep; building height limits including height limits to the fire access route; a requirement for exterior cladding and roof covering to be noncombustible or combustion resistant; additional compartmentalization for large sprinklered spaces such as attics; requiring at least 10 per cent of the building perimeter to be within 15 metres of a fire safety access route; requiring that exit stairwells have a 1.5 hour fire-resistant rating and be of noncombustible construction; and a requirement to meet a higher seismic load than similar noncombustible buildings; and more robust occupancy permit requirements.
