Nova Scotia Building Code & Radon (Quick Summary)
- Since 2010, Nova Scotia has followed the National Building Code rules for radon‑resistant construction in new homes.
- These rules do NOT guarantee low radon levels, but they make future mitigation easier and more affordable.
What’s Built Into New Homes
- Vapour barrier under the foundation slab to help reduce radon entry.
- A radon rough‑in system, usually including:
- A gas‑permeable layer (clean gravel) beneath the slab.
- A vent pipe that runs from below the slab up through the house to above the roofline.
- Sealing of cracks, joints, and penetrations in the foundation.
- The rough‑in pipe capped, sealed, and clearly labeled.
Key Things Homeowners Should Know
- Rough‑ins alone do NOT guarantee safe radon levels – they just make it easier to add an active fan later.
- The building code does not require radon testing or turning the rough‑in into a full system. That part is up to the homeowner.
- Passive systems (no fan) can reduce radon by roughly 30–70%.
- Active systems (with a fan) can reduce radon by about 50–99%.
Why Testing Still Matters
- Even with a rough‑in, you still need to test to know your actual radon level.
- If levels are high, adding a fan to the rough‑in is usually faster and cheaper than starting from scratch.
“This page also links out to official guidance from Health Canada, the Government of Nova Scotia, and U.S. sources like Maine, so homeowners and realtors can dive deeper into the details.”
Radon Guides for Homeowners
Here are trusted radon guides and official resources for homeowners. Start with Health Canada, then explore Nova Scotia and U.S. links below.
Radon – Health Canada (Canada.ca)
Clear, science-based overview of what radon is, health risks, testing guidance, and how to reduce levels in Canadian homes.
Radon – Canadian Cancer Society (Cancer.ca)
Evidence-based overview of how radon increases cancer risk, why testing matters, and steps to lower your exposure.
Radon – Lung.ca (Canadian Lung Association)
Plain-language information on radon, lung health, testing, and how reducing radon lowers your long-term cancer risk.
Much ado about radon – Science.gc.ca blog
Easy-to-read Government of Canada blog post that explains what radon is, why it matters, and what Canadian homeowners can do about it.
Radon home mitigation – CBC News
Real-world story on testing, high radon results, and installing a mitigation system in a Canadian home, with clear photos and homeowner takeaways.
Radon – novascotia.ca
Official Government of Nova Scotia information on radon, local risk in the province, and what homeowners should do about testing and mitigation.
Radon – State of Maine (Maine CDC)
State of Maine public health guidance on radon risk, home testing, and mitigation, useful as a benchmark for mature North American radon programs.
Radon Risk: Nova Scotia vs. Maine (Quick Comparison)
Nova Scotia (HRM focus)
- About 1 in 3 homes in some areas are expected to be above Health Canada’s 200 Bq/m³ guideline.
- Testing rates are still relatively low, so many homes haven’t been checked yet.
- There are only a few specialist providers, leaving room for early leaders to set the standard.
Maine (Benchmark Market)
- Similar geology and radon risk profile to Nova Scotia.
- More mature testing culture and clearer expectations in real estate.
- Shows what a fully developed radon market can look like: regular testing, common mitigation, clearer guidance.
“Maine is a useful benchmark: similar risk, but a more mature radon program. HRM has the same potential as awareness and testing grow.”
Frequently Asked Questions
How long does a radon test take?
Health Canada recommends a long-term test of at least 91 days during the 'heating season' (October to April) for the most accurate representative results. Short-term tests (2–7 days) are available for quick snapshots, such as during real estate transactions.
Is radon really a concern in Nova Scotia?
Yes. Nova Scotia has some of the highest natural radon potential in Canada due to our geology. Research shows that roughly 1 in 3 homes in some areas of the province exceed Health Canada’s guideline, making testing essential for every homeowner.
What happens if my radon level is high?
Radon levels can be effectively reduced using an active soil depressurization system. As a CNRPP certified professional, I can design and install a mitigation system that pulls radon from beneath your foundation and vents it harmlessly outside, often reducing levels by over 90%.
Can I test for radon myself?
Yes, DIY test kits are available and are a great starting point for long-term monitoring. For professional verification, real estate transactions, or mitigation planning, hiring a CNRPP certified professional ensures proper device placement and calibrated measurement accuracy.