What is radon?

If you have recently entered the process of buying or selling a house, you may have just stumbled across the phrase ‘radon affected area’ and have questions about what radon is and why it is coming up on your searches.

When buying a property your solicitor, or your buyer’s solicitor, will run a series of searches for any planning, historical problems in the area, or environmental risks that may affect the home, this may include searches concerning radon. A local surveyor conducting a home survey will also note if the property is in an affected area, and may recommend a specialist survey as part of a home survey report.


So, what is radon ?

Radon is a naturally occurring radioactive gas. It is a colourless, odourless, and tasteless gas found in the air with a propensity to collect in enclosed places, such as houses.

It is formed through the decay of uranium in rocks and soil, with the level of radon found being heavily influenced by the underlying geology in the area, in addition to a building’s construction and the behaviour of the people living in it.

Radon is found everywhere and pretty much every home and building contains some level of radon. For most properties this is low and so the risk to health is low. However, some buildings do have higher levels which can be a cause for concern.

The average level of radon found in UK homes is 20 Bq m-3 (Becquerels per cubic metre of air). The government advises that the risk from radon remains low for anything below 100 Bq m-3.

What are the effects of radon exposure?

Radon is a radioactive gas and, while in most cases the level of exposure to radon is too low to have any effect on people’s health, if there is a high enough concentration of radon in a particular area or building, this can cause significant harm.

This is due to the inhalation of radioactive elements formed from the decay of the radon. They enter the lungs where they continue to decay emitting radiation which is absorbed by the lung tissue, resulting in damage. Radon is the number one environmental cause of cancer, and the second leading cause of lung cancer after smoking.


Why do certain areas or buildings have higher concentrations?

As previously mentioned, the level of radon gas is largely dependent on the type of ground a property is built on as certain types of rock and soil have a higher-than-average uranium content. Radon maps break the country down into 1 km squares and indicate highest radon concentration level found in that square.

Take a look at the UK Radon maps here: https://www.ukradon.org/information/ukmaps

However, this is not the only factor that may affect radon concentration. Radon levels tend to be higher inside buildings than outside. Why is this? The air pressure inside buildings is typically lower than outside, which causes radon to be drawn in through pores and fissures in the ground which can then enter the home through gaps or cracks in the floors and walls.

Buildings with below ground rooms such as basements or cellars, or those built into a hillside, are also considered at higher risk due to the additional surface contact which increases the likelihood of radon permeating the structure.

Additionally, radon can also be released from building materials themselves. Although most new buildings are constructed with radon prevention in mind, there are additional ways you can look to reduce the radon levels in your home.


Do I need to test for radon?

If you are going through a property purchase, your solicitor or buyer’s solicitor may already have applied for a radon risk report which will indicate the level of potential risk for an individual address rather than the kilometre square it is in. However, it does not give the actual radon level in the property itself.

If your property is in a Radon Affected Area and you are concerned about the levels of radon in your home, you can purchase a domestic measurement pack (current cost less than £60). This comprises 2 small plastic detectors that are placed in a living area and a bedroom for three months before being returned to a validated laboratory for testing and analysis. As monitoring takes three months and the results are affected by the way the property is ventilated by the occupants, it can’t be done as part of the process of buying a home.

Find out more at: https://www.ukradon.org/information/measuringradon


Reducing radon in indoor settings

Radon levels within the home are often directly related to the permeability of the building. Therefore, if you are in a ‘radon affected area’ and are concerned about the amount of radon entering your home, sealing any gaps, cracks or openings will help.

You can also reduce radon levels in the home with appropriate ventilation by installing features such as a positive ventilation system which essentially comprises a fan that blows air from the roof space through the building, good natural or fan assisted underfloor ventilation, or an active radon sump with a fan which works best under solid floors.

For more information on radon and radon reduction methods, visit: https://www.ukradon.org/information/

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