Basements are typically classified as being at ‘higher risk’ of containing elevated levels of radon. Additionally, the low atmospheric pressure within a basement creates a greater suction dynamic, drawing gas from the soil into the property.
It’s important to note that materials used for waterproofing are not inherently gas-proof (radon, methane, CO2, CO, etc) in any basement project including conversions (Refer to BS8102:2022 and NCC 2022).
ARPANSA recommends < 200 Bq m⁻³ for households and workplaces.
It is highly advisable to consider positive pressurisation, ventilation (air extraction), installation of gas/air barrier (not the same as a vapour barrier), or using a combination of these methods when higher gas content is detected on site.
