Effective March 8, 2024, the British Columbia Building Code (BCBC) mandates radon mitigation measures in new constructions to reduce indoor radon levels below Health Canada’s guideline of 200 becquerels per cubic metre (Bq/m³). These provisions apply to all new Part 9 buildings (e.g., houses) with conditioned spaces in contact with the ground. For Part 3 buildings (e.g., commercial structures), radon mitigation requirements are outlined in Parts 5 and 6 of the 2024 BCBC. (Bulletin B24-03 BCBC 2024)
City of Burnaby’s “Radon Mitigation Information Guide” provides comprehensive details on radon stack installations, including termination clearances. This guide references Figure 7.2.4.6 from the CAN/CGSB-149.11 standard, which illustrates the required clearances for rooftop radon stack terminations. City of Nanaimo has issued “Radon Control for part 9 Buildings” to clarify requirements.
CAN/CGSB-149.11, “Radon Control Options for New Construction in Low-Rise Residential Buildings,” provides guidelines for mitigating radon ingress in new residential constructions. Following clearances must be maintained to prevent radon gases are safely dispersed away from openings and air intakes. 
- Vertical clearance above the roof at the point of penetration: 0.30 meters
- Vertical clearance above windows or doors: 0.60 meters
- Vertical clearance above mechanical air supply inlets (air intake): 0.90 meters
- Horizontal clearance from windows, doors, or mechanical air supply inlets: 3.00 meters
- Horizontal clearance from a vertical wall that extends above the roof penetrated: 3.00 meters
It’s important to note that the 2024 British Columbia Building Code references CAN/CGSB-149.11 for radon mitigation requirements in new constructions. Specifically, the code mandates compliance with sections 7.1.3 (pipe and fittings), 7.2.4.6 (exterior pipe terminations), and 7.3.4 (active radon reduction system discharges) of the standard.
Recent Comments