Code Library › Volume 1 › Section 9.41 — Additional Requirements for
PART 9 — HOUSING AND SMALL BUILDINGSUpdated for the 2024 Ontario Building Code

9.41.1.1.Application

(1) This Section applies where proposed construction in respect of an existing building will result in any of the following changes of use of all or part of the building: (a) a change of the major occupancy of all or part of a building that is designated with a “Y” in Table 1.3.1.4. of Division C, (b) a suite of a Group C major occupancy is converted into more than one suite of a Group C major occupancy, (c) a farm building or part of a farm building is changed to another major occupancy other than a Group G major occupancy, (d) a building or part of a building is changed to a post-disaster building, (e) the use of a building or part of a building is changed and the previous major occupancy of the building or part of the building cannot be determined, or (f) a farm building or part of a farm building is changed to a Group G, Division 1 major occupancy. (2) For the purposes of this Section and Sentences 11.4.2.1.(1) and 11.4.2.5.(4), the changes of use set out in Clauses (1)(b) to (f) are also deemed to constitute a change in major occupancy. (3) The requirements of this Section are in addition to the requirements of other Parts of the Code as they apply to the proposed construction.

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

Next →9.41.2.1. Change of Use and Compensating Construction

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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.