Radon and basements

Radon is a radioactive gas from the ground, and basements are the part of the house closest to it. The reference level for homes is 200 Bq/m³. A radon sump with a fan costs about €1,200 and cuts levels by about 90%.

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200 Bq/m³the reference level for homes
One thirdof Ireland is a High Radon Area
About 90%cut by a sump with a fan
350lung cancer cases a year linked to radon

What you need to know

About 350 lung cancer cases in Ireland every year can be linked to radon.
A High Radon Area is one where more than 10% of homes are predicted to be above the 200 Bq/m³ reference level. About a third of the country is one, mainly in the south and west.
Radon comes in through cracks in floors and gaps around pipes and cables. A basement has more wall and floor in the ground, so it has more ways in.
Every home built since 1 July 1998 must have a standby radon sump. In High Radon Areas, a radon barrier as well.
Of all the homes the EPA has measured, 14.1% were above the reference level.

Test with a radon detector over three months. The EPA has its radon maps and tests, and it tests again for free after the work.

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Questions we get asked

Is radon worse in a basement?

Usually. The basement has the most contact with the ground. Test the room once it's finished and in use.

How much does a radon sump cost?

About €1,200 for a sump with a fan, within €500 to €2,000. Turning on a standby sump is €500 to €1,200.

Can radon be fixed during a basement conversion?

Yes, and it costs least then: the floor is open, so a barrier and a sump go in with the waterproofing.

Does a radon sump stop damp?

No. A radon sump draws out gas. Water needs the waterproofing and its own sump.

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