The Ontario Building Code | General
4.2.7.1. General
(1) A deep foundation unit shall provide support for a building by transferring loads by end-bearing to a competent stratum at considerable depth below the structure, or by mobilizing resistance by adhesion or friction, or both, in the soil or rock in which it is placed.
In Plain Language
This clause explains how deep foundations (like piles or caissons) actually carry a building's load: either by end-bearing on a strong soil/rock layer well below the structure, or by friction/adhesion along the sides of the foundation unit in the surrounding soil or rock, or a combination of both.
Common Questions
Q: What's the difference between end-bearing and friction piles?
End-bearing piles transfer load down to a strong, competent layer at depth, while friction (or adhesion) piles rely on resistance along the pile's surface within the surrounding soil or rock. This clause allows either method, or both together.
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.