Up to $50,000 in builder-paid radon mitigation.

Yes. The radon coverage was added to the Tarion statutory warranty for agreements of purchase and sale signed on or after February 1, 2021. Up to $50,000 in mitigation costs are covered for the full 7-year warranty period if a C-NRPP certified test shows radon at or above 200 Bq/m³. ¹ Ontario is one of the only provinces in Canada with this protection built into its statutory new home warranty.

For Tarion coverage, yes. The radon clause was added on that date and applies only to agreements signed on or after. Earlier Tarion warranties may have covered radon as a "major structural defect" but without the explicit $50,000 cap. If your home is older than that, you have other options: the Canadian Lung Association's Lungs Matter Grant (up to $1,500 for income-qualified households), the Take Action on Radon 100 Test Kit Challenge for free testing, and the Ontario Renovates Program for low-to-moderate income forgivable loans. See our full grants page.

For a Tarion claim to be accepted, yes. Tarion specifically requires testing by a C-NRPP (Canadian National Radon Proficiency Program) certified professional. DIY alpha-track kits do not qualify, and no Tarion claim built on a DIY result has ever succeeded that we're aware of. The certification ensures the test was done with calibrated equipment under proper closed-house conditions.

Tarion handles disputes through its own inspection process. If a builder disagrees with the result or claims something else caused the high reading, Tarion sends an independent C-NRPP certified inspector to perform their own test. If Tarion's test confirms the high reading, the builder is required to comply. Builder license penalties are severe, so most builders comply once Tarion is involved.

No. The Tarion coverage triggers at 200 Bq/m³ exactly, matching Health Canada's guideline. Below that, the home is considered compliant even if not ideal. We typically recommend a follow-up long-term test (91+ days) for results in the 100 to 200 range, because seasonal variation can push winter readings higher than your initial summer test. If your follow-up test crosses 200, the warranty activates.

This is genuinely ambiguous and depends on Tarion's reading of "agreement of purchase and sale" date. Most pre-construction APS dates are well before close. We recommend you call Tarion directly at 1-877-9-TARION with your APS date and home registration number to confirm before we test. If Tarion confirms coverage, we'll proceed normally. If not, you may still have remedy through the standard Tarion 7-year structural defect clause.

Test booking to written report: 5 to 8 days. Tarion claim submission: same-day after report. Builder response: up to 30 days mandated. Mitigation install: 2 to 4 weeks after builder approves. Post-mitigation verification: 30+ days after install. Total elapsed time from your first call to a fully mitigated home: typically 5 to 12 weeks. Most of it is wait time, not active work.

No. Filing a radon claim has no effect on other Tarion warranty coverage. Each warranty item is independent. You can use your full $50,000 radon mitigation budget AND still claim other warranty items separately.

Absolutely. The Tarion claim form is available to all warranty holders directly through Tarion's MyHome portal. Our claim filing assistance is a free add-on for our testing customers, but you can do it yourself. The only must-have is a C-NRPP certified test report; everything else is paperwork.