HouseDossier
Radon Gas Check

Radon Gas Check UK -
Invisible Risk, Instant Answer

Radon is responsible for around 1,100 lung cancer deaths in the UK every year - yet most buyers never think to check. Instantly see whether any UK property is in a radon indicative area using UKHSA data.

Try a postcode (SW1A 2AA) or “12 SW1A 2AA”. Covers England and Wales.

Free preview always included. Full radon risk report from £9.95.

Why This Matters

Radon Is the UK's Second Biggest Cause of Lung Cancer - and Most People Have Never Heard of It

Radon is a naturally occurring radioactive gas that seeps through the ground and accumulates in enclosed spaces. You cannot see it, smell it, or taste it. In high-risk areas - primarily where granite, limestone, or uranium-rich rocks are found - indoor radon levels can reach many times the recommended action level of 200 Bq/m³.

Public Health England estimates that radon exposure causes approximately 1,100 lung cancer deaths in the UK each year - making it the second biggest cause of lung cancer after smoking. For non-smokers, radon is the single biggest environmental cause of lung cancer.

Around 700,000 homes in the UK are estimated to have radon levels above the action level. The highest concentrations are in Cornwall, Devon, parts of the Peak District, and areas of Scotland with granite geology. Remediation is straightforward and effective - but only if you know the risk exists.

1,100

lung cancer deaths in the UK attributed to radon annually

UK Health Security Agency

700K

UK homes estimated to have radon above the action level

UKHSA / PHE

200 Bq/m³

UK radon action level - remediation strongly recommended above this

UKHSA

£1–2K

typical cost of a radon sump installation

UKHSA / BRE

High-Risk Areas

Where Is Radon Risk Highest in the UK?

Radon risk correlates closely with underlying geology. Areas with granite, limestone, and uranium-bearing rocks have the highest concentrations.

Cornwall & Devon

The highest radon areas in England. Underlain by granite which is naturally rich in uranium. Some properties in Cornwall have radon levels many times the action level.

Peak District (Derbyshire)

Carboniferous limestone geology. Significant radon potential across the Peak District, particularly in older properties with poor sub-floor ventilation.

Northamptonshire & Lincolnshire

Jurassic limestones and mudstones. Elevated risk in parts of these counties, particularly rural properties.

Parts of Scotland

Granite-rich geology in the Scottish Highlands. Some of the highest natural radon levels in the UK occur in rural Highland properties.

This is not an exhaustive list. UKHSA radon mapping covers all of England and Wales. Enter any address below to check whether the specific property location is in a radon indicative area.

What HouseDossier Checks

Radon Risk Data - Straight from the Source

UKHSA Radon Indicative Area Designation

Whether the property's grid reference falls within a UKHSA-defined radon indicative area - the official government measure of whether elevated radon is statistically likely at that location.

Percentage of Homes Above Action Level

The estimated percentage of homes in the 1km grid square that test above 200 Bq/m³. High percentages (20%+) indicate a strong geological driver; lower percentages reflect more localised variation.

Building Regulations Radon Protection

Based on the property's estimated construction era and geographic location, we note whether Building Regulations radon protective measures are likely to be present (required for new builds since 2001 in high-risk areas).

Radon Remediation Guidance

Where elevated risk is detected, the report provides clear, plain-English guidance on the recommended next steps: short-term test, long-term test, and the range of remediation options available.

How It Works

Radon Risk Check in Three Steps

01

Enter the property address

We geolocate the property to a precise grid reference using Ordnance Survey data. Radon risk varies at a very local scale, so postcode-level data is less accurate than grid reference-based mapping.

02

We query the UKHSA radon mapping data

The property's grid reference is checked against the UKHSA 1km grid square radon dataset, which records the estimated percentage of homes above the action level for each square kilometre of England and Wales.

03

Radon risk designation returned with context

You receive a clear radon risk designation: low, moderate, or high. For elevated-risk properties, we explain what the designation means, what a test costs, and what remediation options exist.

Report Preview

What Your Radon Report Includes

  • UKHSA radon indicative area: yes / no
  • Estimated % of homes above 200 Bq/m³ in the 1km grid square
  • Radon risk level: low / moderate / high
  • Recommended action: no action / test recommended / test required
  • Building Regulations radon protection likely present (yes/no)
  • Radon testing guidance and recommended providers
  • Remediation options if testing reveals high levels
  • Indicative remediation cost range
  • BGS geology note (underlying rock type explanation)
  • Plain-English radon health risk summary

Pricing

One Report, One Price

Quick Check

£9.95per report
  • Radon indicative area designation
  • Radon risk level (low/moderate/high)
  • Flood risk
  • EPC rating
  • Sold price history
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£19.95per report
  • Radon testing & remediation guidance
  • BGS geology detail
  • Coal mining & ground risk
  • Full environmental check
  • AI summary & red flags
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FAQ

Radon Gas - Frequently Asked Questions

What is radon gas and why is it dangerous?
Radon is a naturally occurring radioactive gas produced by the decay of uranium in rocks and soils. It is colourless, odourless, and tasteless - undetectable without a test. Radon seeps through cracks and gaps in building foundations and accumulates in enclosed spaces. Prolonged exposure to elevated radon levels is the second leading cause of lung cancer in the UK after smoking, responsible for approximately 1,100 deaths per year according to Public Health England.
What is the radon action level in the UK?
The UK action level - set by the UK Health Security Agency (UKHSA) and Public Health England - is 200 Becquerels per cubic metre (200 Bq/m³). If a property tests above this level, remediation is strongly recommended. The target level for new homes and post-remediation properties is below 100 Bq/m³. The average UK indoor radon level is approximately 20 Bq/m³, but in high radon areas this can be 10–20 times higher.
Does a radon indicative area designation mean my house definitely has high radon?
No. A radon indicative area designation means that a statistically significant proportion of homes in that area have been found to have radon levels above the action level - but individual properties can vary enormously. Two adjacent properties can have very different readings. The indicative area designation tells you that testing is recommended and that the geological risk exists. Only an actual radon measurement (using a two-detector, 90-day test) gives you the specific level in the property.
Who is responsible for providing radon information on a property sale?
Under the Consumer Protection from Unfair Trading Regulations 2008, sellers and estate agents have a duty to disclose material information that would affect a buyer's decision. Radon risk is generally considered material in high-risk areas. Environmental searches provided by solicitors typically flag radon indicative area designations. Our report clearly indicates whether a property is in a radon indicative area under UKHSA mapping.
How do you reduce radon in a property?
The most effective radon reduction method is a radon sump - a small pit dug in the sub-floor void, connected to a pipe and fan that draws radon from beneath the floor slab and vents it above the roof. This can reduce levels by 80–90% and costs approximately £1,000–£2,000 installed. Positive pressure ventilation systems (PIV) can also be effective. Sealing floor joints, improving underfloor ventilation, and installing passive radon sumps are lower-cost first steps.
Is radon covered by building regulations for new homes?
Yes. Since 2001, new homes in the highest radon areas are required to incorporate passive radon protective measures under Building Regulations Part C. Higher-risk areas require more comprehensive active systems. New builds in radon indicative areas will typically have been constructed with at least a radon barrier membrane and may have a passive sump provision. Our report notes construction era, which is relevant to assessing whether building regulations radon provisions are likely to be present.
Does radon affect property insurance or mortgage lending?
Radon designation itself does not typically affect mortgage availability - unlike flood risk, it is not a blanket lender concern. However, some specialist lenders ask environmental questions that include radon. Buildings insurance is generally unaffected by radon status. If a property tests above the action level and remediation is required, you may be able to factor this into your offer price.

Check Radon Risk Now

Don't ignore the invisible risk - check before you buy

UKHSA radon indicative area data for any UK address - instantly.

Try a postcode (SW1A 2AA) or “12 SW1A 2AA”. Covers England and Wales.

Free preview included. Full radon report from £9.95.

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