A note before you read. This article presents general health and home-testing information for homeowners and renters in Terrebonne and the north shore of Montreal, drawn from the published materials of Health Canada, the Institut national de santé publique du Québec (INSPQ), the OACIQ, CARST, and the Canadian Cancer Society. It is not medical advice and not legal advice. See full disclaimers at the bottom of the page.
Terrebonne, a major city in the Lanaudière region on Montreal's north shore, sits on sedimentary bedrock that transitions to the Canadian Shield farther north. Quebec's residential radon prevalence, according to Health Canada's Cross-Canada Survey of Radon Concentrations in Homes (2012), sits at roughly the Canadian average — close to 7% of homes at or above 200 Bq/m³, with significant regional variation.
Whether you live in Terrebonne (the Vieux-Terrebonne, Terrebonne-Ouest, La Plaine, or Lachenaie sectors), in Mascouche, Repentigny, Charlemagne, or anywhere else in southern Lanaudière, radon testing is essential.
The essentials for Terrebonne homeowners and renters
- Health Canada's residential guideline: 200 Bq/m³ (Health Canada — Radon).
- Test your home with a 91-day long-term alpha-track test at the lowest lived-in level, during the heating season (October–April).
- Order a $89 long-term test kit →
- Quebec real estate is regulated by the OACIQ; the latent defect (vices cachés) framework of the Civil Code generally triggers disclosure of known elevated results.
Table of contents
- Why test Terrebonne homes
- What the Quebec and Lanaudière data shows
- How to test your home
- Mitigation in Terrebonne
- Real estate and OACIQ disclosure
- Renters in Terrebonne
- FAQ — Terrebonne-specific questions
- Order your test kit
- Important disclaimers
- Sources and further reading
Why test Terrebonne homes
Terrebonne and southern Lanaudière rest on the sedimentary bedrock of the St. Lawrence Lowlands, transitioning to the Canadian Shield farther north (northern Lanaudière). Uranium-bearing parent material is present in some sub-regions, particularly toward the Shield.
Three factors:
- Transitional geology. Sedimentary in the south, Canadian Shield in the north (northern Lanaudière), with uranium-bearing parent material in some areas.
- Long heating season. Quebec winters mean months of continuous heating operation.
- Housing stock. Terrebonne and the north shore have a large number of single-family and semi-detached homes with full basements used as living space.
What the Quebec and Lanaudière data shows
Health Canada's 2012 Cross-Canada Survey places Quebec at roughly 7% of homes above 200 Bq/m³. The Lanaudière region — particularly the north, where the Canadian Shield predominates — can show higher-than-provincial-average prevalence in some sub-regions.
How to test your home
Per Health Canada (Guide for Radon Measurements in Residential Dwellings), the standard is a long-term test of at least 91 days using an alpha-track detector, at the lowest lived-in level during the heating season (October–April).
For most Terrebonne homes:
- Finished basement if it serves as living space.
- Lowest sleeping level if the basement is unfinished.
- Ground floor only if the home has no basement.
Place the kit at breathing height (1 to 2 metres off the floor). Leave it in place for at least 91 days.
Order your $89 long-term test kit →
Mitigation in Terrebonne
If your test exceeds 200 Bq/m³, the standard Canadian solution is active sub-slab depressurization (SSD). Typical cost: $2,500 to $4,500.
Always use a C-NRPP-certified mitigation professional. Check the C-NRPP directory filtered by Quebec. Terrebonne is well served by C-NRPP-certified contractors from the Greater Montreal area.
For the full guide, see How to choose a licensed radon mitigator in Canada. After mitigation, run an independent post-mitigation test.
Real estate and OACIQ disclosure
Quebec real estate is regulated by the OACIQ. The Seller's Declaration generally requires disclosure of known material defects. The latent defect (vices cachés) framework of the Civil Code is more protective than the common law of other provinces. Consult a Quebec notary or real estate lawyer.
Renters in Terrebonne
Quebec's residential tenancy framework is administered by the Tribunal administratif du logement (TAL). See our Radon for Canadian renters (2026) guide.
FAQ — Terrebonne-specific questions
Is radon a real concern in Terrebonne? Yes — Lanaudière, particularly the north, can show higher-than-provincial-average prevalence. Test your home.
What is the action level for radon in Terrebonne? 200 Bq/m³ — Health Canada's residential guideline.
How do I test my home? Use a 3-month long-term alpha-track test (≥91 days). Cost: $89 all-in for a RadonTest.ca kit.
How much does mitigation cost in Terrebonne? Typical cost: $2,500 to $4,500 for a standard sub-slab depressurization (SSD) system.
Do Quebec sellers have to disclose radon? The latent defect (vices cachés) framework of Quebec's Civil Code and the OACIQ Seller's Declaration generally require disclosure of known material defects.
Does the Tarion warranty cover new homes in Terrebonne? No — Tarion is the Ontario warranty. In Quebec, new-home warranties are administered by the Garantie de construction résidentielle (GCR).
Can I use the Lungs Matter grant in Terrebonne? The Lungs Matter program offers up to $1,500 to eligible Canadian homeowners. Verify directly.
Should I retest after mitigation? Yes — Health Canada recommends a retest after mitigation and after major renovations.
What if my landlord refuses to act? Document everything in writing and consider a recourse to the Tribunal administratif du logement (TAL).
Order your test kit
Order your $89 all-in long-term test kit →
91-day long-term alpha-track test kit. C-NRPP-listed device. Analysed at Lex Scientific in Guelph, Ontario — a Canadian lab, C-NRPP listed, ISO/IEC 17025 accredited by CALA. Tracked Canadian shipping both ways. Written lab report PDF delivered to your inbox.
Shipping throughout southern Lanaudière including Terrebonne, Mascouche, Repentigny, Charlemagne, and surrounding municipalities.
Important disclaimers
Not medical, legal, or warranty advice. Consult qualified Quebec professionals.
Statistics and citations. Taken from Health Canada's 2012 Cross-Canada Survey and the INSPQ's publications. As of May 2026.
Local data. Northern Lanaudière (Canadian Shield) can show higher-than-provincial-average prevalence. Variability from one home to the next is large. Test your home.
Mitigation cost. The $2,500 to $4,500 range reflects typical Canadian pricing in 2026.
Lungs Matter grant. Eligibility may change. Verify directly at lung.ca before relying on the program.
No diagnosis or treatment claims. RadonTest.ca sells radon test kits. We do not diagnose, treat, or prevent any disease.
No warranty as to completeness. RadonTest.ca makes no warranty as to the completeness or accuracy of the information presented here and accepts no liability for decisions made in reliance on this article.
Sources and further reading
Quebec-specific
- INSPQ — Radon
- OACIQ
- Tribunal administratif du logement (TAL)
- Garantie de construction résidentielle (GCR)
Health Canada / national
- Health Canada — Radon
- 2012 Cross-Canada Survey
- Canadian Cancer Society — Radon
- Canadian Lung Association — Lungs Matter
- C-NRPP — Find a Professional
- CARST
- Take Action on Radon
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