Code Library › Volume 1 › Section 9.3 — Materials, Systems and Equipment
PART 9 — HOUSING AND SMALL BUILDINGSUpdated for the 2024 Ontario Building Code

9.3.1.6.Compressive Strength

(See also Article 9.12.4.1., Sentence 9.15.4.2.(1) and Article 9.18.6.1.) (1) Except as provided elsewhere in this Part, the compressive strength of unreinforced concrete after 28 days shall be not less than, (a) 32 MPa for garage floors, carport floors and all exterior flatwork, (b) 20 MPa for interior floors other than those for garages and carports, and (c) 15 MPa for all other applications. (2) Site-batched concrete used for garage floors, carport floors and exterior flatwork shall have air entrainment of 5 to 8%.
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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.