Question 1

What is the radon risk level in RG21?

Accepted Answer

The radon potential in RG21, Hampshire is classified as High by the British Geological Survey. Approximately 3–5% of homes in this area may have radon levels above the UK action level of 200 Bq/m³ — compared to a national average of around 1%. The district covers 16 BGS grid squares. Note: some grid squares within RG21 reach class 4, meaning radon risk is not uniform across the district.

Question 2

Do I need a radon test in RG21?

Accepted Answer

Radon levels in RG21 are above the national average (3–5% of homes). UKHSA recommends that homeowners in this area test for radon, particularly in ground-floor and basement rooms. A 3-month postal detector is the standard approach.

Question 3

How do I reduce radon levels in my RG21 home?

Accepted Answer

If a radon test in RG21 shows levels above 200 Bq/m³, the most effective mitigation is a radon sump — a pipe and fan system installed beneath the floor that extracts radon before it enters the building. This typically costs £500–£1,500 and reduces radon by 80–90%. While Hampshire has variable radon levels, targeted remediation is effective regardless of area. Note: parts of RG21 reach radon class 4 — higher than the district average — so risk within the postcode district is not uniform. Improved underfloor ventilation and positive pressure ventilation systems are lower-cost alternatives. See our full guide on how to test and what to do if your levels are elevated.

Radon Risk in RG21

Recommended Actions for RG21

What does this mean?

Nearby Postcode Areas

Get a Radon Test for RG21