Radon in Brantford
Brantford is a Grand River city with a deep stock of early 20th-century homes in its older wards and fast-growing neighbourhoods in West Brant and the north end.
Brantford radon guide
Radon in Brant & Brantford
Grand River valley city and towns, from Brantford’s older wards to Paris’s cobblestone heritage and new growth in St. George.
Brantford and the County of Brant follow the Grand River and its tributaries. Brantford’s older wards (Eagle Place, Holmedale, Echo Place) are full of early 20th-century homes, while West Brant and the north end add newer subdivisions. Paris, St. George and Burford are growing quickly too.
The Grand River has cut through layers of glacial outwash, leaving sand and gravel terraces through Brantford and Paris. Moraines around Paris and St. George add more coarse, gravelly soil. These are some of the most permeable soils in our service area, and they let soil gas reach foundations easily.
Paris is known for its 19th-century cobblestone buildings, and many older homes in the region sit on stone or rubble foundations. Newer homes in West Brant and around Paris are larger and more airtight. Different houses, same advice: test the lowest lived-in floor for at least three months.
Public health: Grand Erie Public Health.
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)
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
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)
Local factors
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.
The till and gravel left by glaciers here includes ground-up rock carried south from the Canadian Shield. Uranium travels with it, so radon can form close to your footings even where the bedrock itself is low in uranium.
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.
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.
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.
Communities
Brantford is a Grand River city with a deep stock of early 20th-century homes in its older wards and fast-growing neighbourhoods in West Brant and the north end.
Brantford radon guide
Paris is famous for its 19th-century cobblestone buildings and its spot where the Nith meets the Grand.
Paris radon guide
Questions
Brantford has no published neighbourhood-level radon data, and the early national survey tested too few homes to judge any one city. What we do know: about 1 in 8 Ontario homes test at or above the guideline, and Brantford’s gravelly river soils let soil gas move easily. Testing is the only way to know.
Often a little more work. Stone and rubble foundations have more openings, so we pay extra attention to sealing, and sometimes add a second suction point or treat a crawlspace separately. Sub-slab depressurization still works well in most of them.
C-NRPP certified testing and mitigation across Brantford, Paris.