London & Middlesex
Radon testing and mitigation in Strathroy, Ontario
Strathroy-Caradoc sits 30 minutes west of London, where two radon factors overlap: a uranium-bearing shale band underground and sandy, permeable soils at the surface. Here’s what’s known about radon in Strathroy, and how to find out about your home.
- Region
- London & Middlesex
- Population
- about 24,000 (Strathroy-Caradoc)
- Public health
- Middlesex-London Health Unit
- Local factors
- 4 reasons to test
Is radon a problem in Strathroy?
Radon can exceed Health Canada’s 200 Bq/m³ guideline in any Strathroy 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, nearby uranium-bearing shale, sandy or gravelly soils and rural drilled wells are reasons to test. A 91-day test is the only way to know your home’s level.
Radon in Strathroy
Strathroy-Caradoc sits 30 minutes west of London, where two radon factors overlap: a uranium-bearing shale band underground and sandy, permeable soils at the surface. It’s a small town with a lot of rural homes around it, many on private wells.
The ground under Strathroy
The Kettle Point Formation, a black shale that Ontario Geological Survey drill core puts at over 30 ppm uranium on average, runs beneath this part of Middlesex on its way from Lake Huron toward Lake Erie. South and east of town, around Mount Brydges, the Caradoc Sand Plain gives the ground a sandy, fast-draining character that lets soil gas travel.
Strathroy’s homes
Downtown Strathroy has plenty of older brick homes. New subdivisions on the town’s edges and in Mount Brydges are bigger and tighter. Out in the township, farmhouses often combine fieldstone foundations with drilled wells, both of which raise radon risk.
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 Strathroy
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.
Strathroy: collecting results. Already tested? Check your number and share it anonymously when you book.
Local factors
What can push radon up in Strathroy
Not a prediction for any single home, just the reasons a test is worth it here.
Uranium-bearing shale nearby
Black shale is the most common uranium source rock in southern Ontario. The Kettle Point shale that runs under Lambton and western Middlesex and Elgin averages over 30 ppm uranium in Ontario Geological Survey drill core, roughly ten times a typical rock.
Sandy or gravelly soils
Sand and gravel let soil gas move freely and over longer distances. More of the radon formed in the ground can reach the air around your foundation instead of decaying in place.
Rural homes on drilled wells
A 2024 national study of over 42,000 homes found rural residents were exposed to about 30% more radon than urban residents, with most of the gap linked to drilled wells. Researchers suspect gas travels up the gap around the well casing.
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.
Where we work
Strathroy neighbourhoods and nearby communities
- Strathroy
- Mount Brydges
- Melbourne
- Caradoc
- Adelaide Metcalfe
- Kerwood
- Napier
Nearby: Radon in Komoka · Radon in London · Radon in Sarnia · Radon in Chatham
How it works
From test to fix
- Book
Tell us about your Strathroy 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 Strathroy: FAQ
Is radon a problem in Strathroy?
Radon can exceed Health Canada’s 200 Bq/m³ guideline in any Strathroy 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, nearby uranium-bearing shale, sandy or gravelly soils and rural drilled wells are reasons to test. A 91-day test is the only way to know your home’s level.
Is there uranium under Strathroy?
Western Middlesex is underlain by the Kettle Point Formation, a black shale that Ontario Geological Survey core samples measured at over 30 ppm uranium on average, roughly ten times typical rock. It sits beneath thick glacial deposits, so its effect varies from site to site. Testing tells you what reaches your basement.
Do homes on wells around Strathroy need a different test?
The air test is the same: a 91-day detector on the lowest lived-in floor. Research suggests well casings can act as a pathway for soil gas, so rural homes are worth testing even when town homes nearby are low.
Do you offer radon testing and mitigation in Strathroy?
Yes. We test and mitigate homes throughout Strathroy, including Strathroy, Mount Brydges, Melbourne, Caradoc, Adelaide Metcalfe and nearby. Call (226) 271-4667 or book online.
Radon is fixable. First, know your number.
Serving Strathroy, Komoka, London, Sarnia and Chatham.