Code Library › Volume 1 › Section 3.1 — General
PART 3 — FIRE PROTECTION, OCCUPANT SAFETY AND ACCESSIBILITYUpdated for the 2024 Ontario Building Code

3.1.2.1.Classification of Buildings

(1) Except as permitted by Articles 3.1.2.3. to 3.1.2.7., every building or part thereof shall be classified according to its major occupancy as belonging to one of the Groups or Divisions described in Table 3.1.2.1. (See Note A-3.1.2.1.(1)) (2) A building intended for use by more than one major occupancy shall be classified according to all major occupancies for which it is used or intended to be used. Table 3.1.2.1. Major Occupancy Classification Forming Part of Sentences 3.1.2.1.(1), 3.1.2.2.(1) and 3.11.2.1.(3) Group Division Description of Major Occupancies A 1 Assembly occupancies intended for the production and viewing of the performing arts A 2 Assembly occupancies not elsewhere classified in Group A A 3 Assembly occupancies of the arena type A 4 Assembly occupancies in which occupants are gathered in the open air B 1 Detention occupancies B 2 Care and treatment occupancies B 3 Care occupancies C --- Residential occupancies D --- Business and personal services occupancies E --- Mercantile occupancies F 1 High-hazard industrial occupancies F 2 Medium-hazard industrial occupancies F 3 Low-hazard industrial occupancies

This provision includes a table — formatting is preserved from the source; refer to the official code for the authoritative layout.

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Code text is reproduced for reference from the Ontario Building Code (O. Reg. 163/24, 2024 Building Code Compendium). This page is provided for general information and is not an official copy. Always verify requirements against the official Ontario Building Code and confirm with your local building department.