Radon can affect buildings of any age, type or size.
If you own your home, it is your own choice whether you want to test for radon and if high levels are found, whether you want to take any remedial action.
Radon Testing in Homes
Radon testing should be carried out within the main living areas and at least one bedroom. This is to ensure that the radon concentration within the areas that are most occupied are ascertained.
In an average-sized home, two detectors will usually be sufficient (one for a living room and one for a bedroom).
If the property is very large, has a basement or has had extensions built at different points in time, more detectors may be required to gain a full picture.
Under normal circumstances, radon testing should be carried out over a three month period. This is because radon levels fluctuate constantly and to gain an accurate result, the average over several months is required.
Radon levels vary from season to season, with the highest levels usually present during the winter months. Radon testing can be carried out at any point during the year and the testing laboratory will apply a seasonal ‘correction’ factor to take account of this.
Radon Remediation in Homes
There are two main remediation techniques available for lowering your radon levels: installing a radon sump or introducing positive pressure. Both techniques involve manipulating the pressure difference between the soil and the accommodation.
A radon sump is a popular and effective choice when it comes to radon mitigation and is effective in situations where there are high radon concentrations. A void is created beneath the building which effectively becomes the lowest point of pressure. This means that gas in the soil will be drawn towards it. Once the gas has reached the void it can be safely vented away from the property via an exhaust pipe incorporating a fan. The exhaust pipe will discharge any harmful gases a safe distance from the property well away from doors and windows, usually above eaves level.
New buildings in radon affected areas often have a radon sump incorporated under the floor at the time of construction, ready to be brought into use if testing shows it is necessary. A perforated sump box is usually installed centrally beneath the building with pipework capped-off beside an external wall. To activate the sump, a fan can be fitted to the pipework and the exhaust pipe extended.
The second method of radon reduction, positive pressure, involves the installation of a special fan in an attic or a perimeter wall if a roof void is not present. The fan draws clean air into the property and disperses it to very gently pressurise the building. The increase in pressure is very slight and not perceptible. This will inhibit radon from the soil from being ‘sucked’ inside. Positive pressure also has the side benefit of improving general indoor air quality, particularly by lowering the relative humidity so any condensation issues are often solved as a consequence.