Code Library › Volume 1 › Section 9.12 — Excavation
PART 9 — HOUSING AND SMALL BUILDINGSUpdated for the 2024 Ontario Building Code

9.12.1.1.Removal of Topsoil and Organic Matter

(1) The topsoil and vegetable matter in all unexcavated areas under a building shall be removed. (2) In localities where termite infestation is known to be a problem, all stumps, roots and other wood debris shall be removed from the soil to a depth of not less than 300 mm in unexcavated areas under a building. (3) The bottom of every excavation shall be free of all organic material.
Next →9.12.1.2. Standing Water

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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.