How to Check Radon Risk Before Buying a House

Check radon risk in four steps

• Open the UKHSA radon map service on gov.uk.
• Enter the postcode of the property you are considering.
• Read the indicative radon band shown, which estimates the chance that homes in that area have elevated radon.
• If the area is a higher band, plan to test the actual property with a radon detector after purchase, as area data is only indicative.

What the radon band means

Radon is a natural radioactive gas that seeps from the ground and can build up indoors. UKHSA maps the country into bands that estimate the proportion of homes in an area expected to be above the radon action level. A higher band means a greater chance, not a certainty, that a given home is affected.

Because the band describes an area rather than a specific building, the only way to know the true level in a particular house is to measure it with a radon detector left in place for a period of time.

What to do if the risk is higher

A higher radon band is not a reason to abandon a purchase. Elevated radon can usually be reduced with simple measures such as improved under-floor ventilation or a radon sump. If you buy in a higher band area, order a radon test and follow UKHSA guidance on reducing levels if needed.

Seeing radon in your property report

The free UKHSA map is useful but only gives an area band. HomeBuyerCheck Premium includes the UKHSA Radon Affected Area band for the specific address in the same report as flood, ground stability, coal and HM Land Registry ownership, so you can weigh radon alongside the other ground risks rather than checking it in isolation.