Reducing your risk

The ground is the main source of radon. The aim of remedial work is to reduce radon levels in the home as low as possible. There are several methods that can reduce high radon levels in homes.

Radon sump

An active radon sump, fitted with a fan, is the most effective way to reduce indoor radon levels. Sumps work best under solid floors and under suspended floors if the ground is covered with concrete or a membrane. Occasionally, passive sumps without a fan may reduce radon levels.

Positive Ventilation

A small quiet fan blows fresh air, usually from the roof space, into the home.

Natural under-floor ventilation

Many homes have a suspended ground floor with a space underneath. Good ventilation of this space can reduce radon concentrations in the home.

Active under-floor ventilation

A fan is used to either continuously blow air into or extract air out from the space below a suspended floor. This can be used when natural under-floor ventilation is inadequate to reduce radon level.

Details of methods are found on separate pages accessible by clicking the title link.

Remedial methods

Some simple actions such as sealing around loft-hatches, sealing large openings in floors and extra ventilation of the living space do not reduce radon levels on their own. When combined with other effective measures, they can improve the reduction of radon levels. Completely sealing floors is difficult and can cause rot in wooden floors. The diagram below is intended as a guide. The Environmental Health Department of your local council may be able to offer advice. For levels in excess of 1000 Bq m^-3 you may wish to contact HPA for advice.

Remedial costs

Costs depend on many factors including the complexity of the building and whether any of the work can be done by DIY. The table below shows approximate costs for measures installed by a contractor (apart from the DIY sump).



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