Code Library › Volume 1 › Section 9.27 — Cladding
PART 9 — HOUSING AND SMALL BUILDINGSUpdated for the 2024 Ontario Building Code

9.27.11.1.Material Standards

(1) Steel sheet cladding, including horizontal and vertical strip steel siding, flashing and trim accessories, shall (a) have a minimum thickness of 0.33 mm, and (b) conform to CSSBI 23M, “Standard for Residential Steel Cladding.” (See Note A-9.27.11.1.(1)) (2) Horizontal and vertical strip aluminum siding, including flashing and trim accessories, shall conform to CAN/CGSB-93.2-M, “Prefinished Aluminum Siding, Soffits and Fascia, for Residential Use.” (See Note A-9.27.11.1.(2) and (3)) (3) Aluminum sheet cladding shall conform to CAN/CGSB-93.1-M, “Sheet, Aluminum Alloy, Prefinished, Residential,” and shall have a thickness of not less than 0.58 mm, except that siding supported by backing or sheathing shall have a thickness of not less than 0.46 mm. (See Note A-9.27.11.1.(2) and (3))
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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.