The Ontario Building Code | Backfilling
4.2.5.8. Backfilling
(1) Where an excavation is backfilled, the backfill shall be placed so as to,
(a) provide lateral support to the soil adjacent to the excavation, and
(b) prevent detrimental movements.
(2) The material used as backfill or fill supporting a footing, foundation or a floor on gradeshall be of a type that is not subject to detrimental volume change with changes in moisture content and temperature.
4.2.6. Shallow foundations
In Plain Language
Where an excavation is backfilled, the backfill must be placed to provide lateral support to the adjacent soil and prevent detrimental movement, and the backfill material itself must meet specific suitability requirements.
This is a plain-language summary of the 2012/2017 Ontario Building Code text above, for general understanding only and not a substitute for the Code. Always confirm current requirements against the 2024 edition (O.Reg. 163/24) or a qualified professional before construction.