The Ontario Building Code | Fire Containment in Basements
220.127.116.11. Fire Containment in basements
(1) Except as permitted by Sentences (2) and 18.104.22.168.(3), in a building in which an automatic sprinkler system is not required to be installed by Articles 22.214.171.124. to 126.96.36.199., every basement shall,
(a) be sprinklered, or
(b) be subdivided into fire compartments not more than 600 m2 in area by a fire separation having a fire-resistance rating not less than that required for the floor assembly immediately above the basement.
(2) An open-air storey need not conform to Sentence (1).