Ministry of the
Solicitor General

Amendments to Ontario’s Building Code Allowing Mid-Rise Wood Frame Buildings

Communiqué du commissaire des incendies

Amendments to Ontario’s Building Code Allowing Mid-Rise Wood Frame Buildings

Communiqué 2014-18

October 22, 2014

On September 23, 2014, Ontario Regulation 191/14 was filed to amend Ontario’s Building Code (Ontario Regulation 332/12) to allow for the construction of wood frame buildings up to six storeys, an increase from the previous limit of four storeys. The amendments will take effect on January 1, 2015, and will be applicable only to buildings used for major occupancies classified as Group C, residential occupancies, or Group D, business and personal services occupancies.

The changes follow consultations in 2010, 2011 and 2013 led by the Ministry of Municipal Affairs and Housing with a broad range of stakeholders, including the Ontario Association of Fire Chiefs, the Fire Fighters Association of Ontario, the Ontario Professional Fire Fighters Association and the Ontario Municipal Fire Prevention Officers Association. In 2014, a 45-day public consultation resulted in over 150 stakeholders providing input.

The new changes support alternative construction options in the Building Code that provide for flexibility while taking into account occupant and firefighter safety.

In order to improve occupant and firefighter safety, the new provisions introduce many fire safety enhancements that are not currently required for four-storey wood frame buildings, including the following:

  • installation of automatic sprinkler systems to the NFPA 13 standard;
  • installation of sprinklers for all balconies over 610 mm in depth;
  • building height limits, including height limits in relation to the fire access route;
  • minimum of 10% of building perimeter must be within 15 metres of a street or fire access route;
  • requirement for exterior cladding and roof covering to be non-combustible or combustion resistant;
  • additional fire protection measures for concealed spaces such as attics;
  • requirement that exit stair fire separations have a 1.5 hour fire-resistance rating and be of non-combustible construction;
  • stricter requirements relating to emergency power supply for fire alarm system and emergency lighting;
  • masonry or concrete firewalls between mid-rise wood buildings and adjoining buildings with no automatic sprinkler systems;
  • limitations in other major occupancies permitted in the building:
  • fire resistance rating of at least 2 hours between major occupancies classified as Group A, Division 2, and major occupancies classified as Group C or Group D;
  • granting of occupancy permits only after all fire safety systems are installed and operational throughout the building.

Mid-rise wood construction buildings are common in parts of Europe, such as Scandinavia and the United Kingdom, and are permitted in several jurisdictions in North America. In 2009, British Columbia amended its Building Code to allow six-storey (mid-rise) wood frame residential buildings. Approximately 50 have been built since that time.

During the consultation process, concerns were raised by fire service stakeholders regarding the potential vulnerability of wood frame buildings during the construction process. To address these concerns, the Ministry of Municipal Affairs and Housing will initiate a review to determine the adequacy of current standards and guidelines and consult with the Office of the Fire Marshal and Emergency Management (OFMEM) and the Ministry of Labour as part of its stakeholder engagement strategy.

Enquiries regarding mid-rise wood construction buildings should be directed to Technical Services, OFMEM; staff members can be reached by e-mail at or by telephone at (416) 325-3100 or 1-800-565-1842.