The Ontario Building Code | Drainage
9.18.5.1. drainage
(1) Except where it can be shown to be unnecessary, the ingress of water into a crawl space shall be controlled by grading or drainage.
(2) drainage of foundation walls shall conform to Article 9.14.2.1.
(3) drainage of the ground cover or floor-on-ground in the crawl space shall conform to Subsection 9.16.3.
(4) Drains shall conform to Section 9.14.
9.18.6. Ground Cover