Appendix B Rule 12-3000

Sealing around outlet boxes and cables to provide an air barrier may be required. Requirements for air
and vapour barriers are in the National Building Code of Canada, Subsections 9.25.3 and 9.25.4

Source: Appendix B Rule 12-3000, CSA C22.1:21, Canadian Electrical Code, Part 1 (25th Edition), Safety Standard for Electrical Installations. © 2021 Canadian Standards Association. Please visit