Moisture Protection for Interior Finishes

(1)  The interior surface of foundation walls below ground level shall be protected by means that minimize the ingress of moisture from the foundation wall into interior spaces where,

    (a)   a separate interior finish is applied to a concrete or unit masonry wall that is in contact with the soil, or

    (b)   wood members are placed in contact with such walls for the installation of insulation or finish.

    (2)  Except as provided in Sentence (3), where the protection of interior finishes required in Sentence (1) consists of membranes or coatings,

    (a)   the membrane or coating shall extend from the basement floor surface up to the highest extent of the interior insulation or finish, but not higher than the exterior finished ground level, and

    (b)   no membrane or coating with a permeance less than 170 ng/(Pa·s·m2) shall be applied to the interior surface of the foundation wall above ground level between the insulation and the foundation wall.

    (3)  Where insulation functions as both moisture protection for interior finishes and as a vapour barrier in accordance with Subsection 9.25.4., it shall be applied over the entire interior surface of the foundation wall.

Article Ontario Regulation 332/12 Building Code,   Information published by for educational purposes only.