Niagara Region
Radon testing and mitigation in Niagara-on-the-Lake, Ontario
Niagara-on-the-Lake holds some of Ontario’s oldest homes. Here’s what’s known about radon in NOTL, and how to find out about your home.
- Region
- Niagara Region
- Population
- about 19,000
- Public health
- Niagara Region Public Health
- Local factors
- 4 reasons to test
Is radon a problem in NOTL?
Radon can exceed Health Canada’s 200 Bq/m³ guideline in any NOTL home. No published local data rules any neighbourhood in or out. Across Ontario, about 1 in 8 homes tested at or above the guideline in the 2024 national survey. Locally, century-home foundations, converted cottages and crawlspaces and cracking clay soils are reasons to test. A 91-day test is the only way to know your home’s level.
Radon in NOTL
Niagara-on-the-Lake holds some of Ontario’s oldest homes. The Old Town was rebuilt after it burned in 1813, and many houses date from the decades after. Virgil, St. Davids and Glendale add newer subdivisions, and wine country fills the rest.
The ground under NOTL
NOTL lies on the Iroquois Plain between Lake Ontario and the Escarpment at Queenston: lake sands, silts and clays over red shale. The ground is generally flat, with sandier soils near the lake and river.
NOTL’s homes
Heritage homes with stone foundations, crawlspaces and dirt-floor cellars are common in the Old Town, and they often need careful, low-visibility mitigation. Newer homes in Virgil and Glendale are built to modern codes but still need a test.
What the data says
Ontario homes at or above Health Canada’s 200 Bq/m³ guideline in the 2024 Cross-Canada Survey, more than double the share found a decade earlier.Source: Cross-Canada Survey of Radon Exposure in the Residential Buildings of Urban and Rural Communities (2024)
Roughly how many homes per health region the first national survey (2009–2011) could test. Too few to clear any neighbourhood, which is why public maps can’t tell you about your house.Source: Health Canada — Cross-Canada Survey of Radon Concentrations in Homes, Final Report (2012)
Higher average radon exposure for rural residents than urban residents in a 2024 national study of 42,051 homes, mostly linked to drilled wells.Source: Goodarzi et al., Scientific Reports (2024) — rural communities and drilled-well annuli
Local results
Building a real radon picture for NOTL
Public radon data for Southern Ontario towns is thin. The national surveys tested only a handful of homes per area. So we’re building our own: anonymized long-term results from homes we test, published by area once there are at least 30, so no single home can be identified and small samples can’t mislead.
NOTL: collecting results. Already tested? Check your number and share it anonymously when you book.
Local factors
What can push radon up in NOTL
Not a prediction for any single home, just the reasons a test is worth it here.
Century homes
Fieldstone, rubble and early concrete foundations, earth-floor cellars and open sumps give radon many ways in. Older doesn’t mean safer: these homes still need a test.
Cottages and crawlspaces
Lakeshore cottages converted to year-round homes often sit on crawlspaces, piers or patched slabs. Once winterized and heated, they can start pulling in soil gas they never did as summer places.
Clay plains
Dense clay slows soil gas, but it cracks in dry spells. Gas then follows the easiest route: the gravel backfill, weeping tile and utility trenches that lead straight to a basement.
New, airtight construction
Canadian research shows newer homes have tended to test higher than older ones. Bigger, taller and tighter homes create a stronger stack effect that draws soil gas in through the slab.
Where we work
NOTL neighbourhoods and nearby communities
- Old Town
- Chautauqua
- Virgil
- St. Davids
- Queenston
- Glendale
- McNab
Nearby: Radon in St. Catharines · Radon in Niagara Falls · Radon in Thorold
How it works
From test to fix
- Book
Tell us about your NOTL home. We reply within one business day.
- Test for 91+ days
A certified technician places long-term detectors on your lowest lived-in floor. You get an early reading at 2 weeks.
- Get your result
Lab-verified average, explained against Health Canada’s guideline.
- Fix it if it’s high
A sub-slab system designed for your foundation, at a fixed price, with results guaranteed.
Questions
Radon in NOTL: FAQ
Is radon a problem in NOTL?
Radon can exceed Health Canada’s 200 Bq/m³ guideline in any NOTL home. No published local data rules any neighbourhood in or out. Across Ontario, about 1 in 8 homes tested at or above the guideline in the 2024 national survey. Locally, century-home foundations, converted cottages and crawlspaces and cracking clay soils are reasons to test. A 91-day test is the only way to know your home’s level.
Can radon systems be installed in heritage homes?
Yes. Mitigation is mostly invisible from the street when planned well: interior pipe routes through closets or chases, fans in attics or garages, and careful sealing of stone foundations. Heritage-designated properties may need approval for exterior changes, which we’ll flag early.
My house has a dirt-floor cellar. What are the options?
We typically cover the earth with a sealed, heavy-duty membrane and depressurize beneath it, or pour a new slab with a suction point. Both approaches are described in Canada’s radon mitigation standard.
Do you offer radon testing and mitigation in NOTL?
Yes. We test and mitigate homes throughout Niagara-on-the-Lake, including Old Town, Chautauqua, Virgil, St. Davids, Queenston and nearby. Call (226) 271-4667 or book online.
Radon is fixable. First, know your number.
Serving NOTL, St. Catharines, Niagara Falls and Thorold.