OBC Amendments allow mid-rise wood-frame construction in Ontario

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.