Code Library › Volume 1 › Section 9.13 — Dampproofing, Waterproofing and
PART 9 — HOUSING AND SMALL BUILDINGSUpdated for the 2024 Ontario Building Code

9.13.2.3.Preparation of Surface

(1) The area in which dampproofing is to be carried out shall be kept free of water during the application and curing of the dampproofing system. (2) The surface to be dampproofed shall be prepared in accordance with the instructions of the dampproofing material manufacturer. (3) Where the dampproofing material is to be applied on insulating concrete form (ICF) walls, the instructions of the ICF wall manufacturer shall be followed. (4) Unit masonry walls to be dampproofed shall be parged on the exterior face below ground level with not less than 6 mm of mortar conforming to Section 9.20. coved over the footing. (5) Concrete walls to be dampproofed shall have holes and recesses sealed with cement mortar or a mastic or sealant that is suitable for vertical applications and compatible with the dampproofing material. (6) The surface required to be dampproofed shall be clean and dry and free of ice, snow, frost, dust, dirt, oil, grease, cracks, projections, depressions, loose particles and debris that could be detrimental to the performance of the membrane to be applied.
← Previous9.13.2.2. Dampproofing MaterialsNext →9.13.2.4. Application of Dampproofing Material

Common questions about this part of the code

When is waterproofing required instead of dampproofing for a foundation in Ontario?What are the radon and soil gas control requirements for new houses in Ontario?Does foundation dampproofing go on the inside or outside of the wall in Ontario?

Understand this provision in seconds

BUILDAiD Assist explains any article of the building code in plain English — with exact citations, exceptions and related requirements.

Try BUILDAiD Beta

Code text is reproduced for reference from the Ontario Building Code (O. Reg. 163/24, 2024 Building Code Compendium). This page is provided for general information and is not an official copy. Always verify requirements against the official Ontario Building Code and confirm with your local building department.