Code Library › Volume 1 › Section 9.16 — Floors-on-Ground
PART 9 — HOUSING AND SMALL BUILDINGSUpdated for the 2024 Ontario Building Code

9.16.2.2.Support of Floors

(1) Material that is susceptible to changes in volume due to variations in moisture content or chemical-microbiological oxidation shall not be used as fill beneath floors-on-ground in a concentration that will damage the building to a degree that would adversely affect its stability or the performance of assemblies. (See also Article 9.4.4.4. and Note A- 9.4.4.4.(1)) (2) Material that is susceptible to changes in volume due to freezing shall not be used as fill beneath floors-on-ground that will be subjected to freezing temperatures. (See also Article 9.4.4.4. and Note A-9.4.4.4.(1)) (3) Except as provided in Sentence (4), fill beneath floors-on-ground shall be compacted. (4) Fill beneath floors-on-ground need not be compacted where the material is clean coarse aggregate containing not more than 10% of material that will pass a 4 mm sieve.
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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.