The Ontario Building Code | Compacting or Filling With Concrete

9.12.4.1. Compacting or Filling With Concrete

(1) Thesoil in trenches beneath footings for sewers and watermains shall be compacted by tamping up to the level of the footing base, or shall be filled with concrete having a strength not less than 10 MPa to support the footing.

Section 9.13. Dampproofing, waterproofing and soil Gas Control

9.13.1. General