When to take action to protect your home

If you have measured the radon level in your home over a three month period and if it is above the national Reference Level of 200 Bq/m³, then you should consider taking action to reduce it.

What you can do if your home has high levels of radon

There are a number of ways to reduce the levels of radon in your home. Many of these are simple to install and inexpensive.

Many radon reduction techniques, often called radon remediation, can be undertaken by DIY enthusiasts or your local building firm.

For more complex situations it may be necessary to consult a contractor specialising in this type of work who will be able to give you specific advice about the most suitable solution for yourself and for your home.

Radon remediation works either by preventing radon entering your home from the ground underneat or by removing the radon after it has entered your home.

The RPII has a list of companies that offer a radon remediation service. This list has been compiled for information only and the RPII does not approve or authorise the services provided by these companies.

To help you choose a remediation company, you should consider the following:

• Get a few quotes to enable you to make comparisons and to help ensure you get the best value
• If the contractor gives references try to talk to the person who gave the reference or see the work for yourself
• Has the contractor been recommended to you?
• Do you know a local builder or contractor that may be able to do the job for you?
• Discuss the following with the contractor:
  • Post remedial measurements
  • Fan maintenance (for active sumps)
  • Costs of running fans (for active sumps)
  • Retesting after significant building work is completed on the home

No matter which method you choose, it is important to have your home re-tested after the work has been completed, to ensure that it has been successful in reducing the level in your home to below 200 Bq/m³. The RPII provides a free post-remediation service to homeowners.

Normally remediation is successful at the first attempt.  However, sometimes more work is needed to reduce the radon levels to below 200 Bq/m³.  Therefore you should agree with your contractor what steps may be taken if the radon levels remain high.

There is no absolute certainty that radon will be reduced to below 200 Bq/m³ even following a number of remediation attempts.  While this rarely happens, it is important to note that any significant reduction in radon levels will reduce your risk of lung cancer even if the levels are not reduced below 200 Bq/m³.

The main methods of radon remediation (reduction)

The main methods of radon remediation are described in the booklet Understanding Radon Remediation – A Householder’s Guide

However, if you need more detailed information about these radon remediation methods you should consult the booklet Radon in Buildings - Corrective Options or a specialist radon remediation contractor.

The most common methods of reducing or preventing high radon concentrations in your home are:

1. Installing an active radon sump (sub-floor depressurisation).  This is the most effective method of reducing radon and the most common remediation method in Ireland.

• A sump can be installed within a  day and with very little disruption to the house as the work is carried out outside the house.
• The work typically costs about €1100, but this can range from €800 to €2000, depending on the complexity of the work. 
• The running cost of the fan is about €90 per year, (assuming a 70 watt fan is used).
• This method can reduce the highest radon concentrations by typically 90% but this may range from 60% to 99%.

2. Increasing indoor ventillation

• This can reduce radon levels by up to 50% and so can be suitable for homes with up to 400 Bq/m³ of radon.

Homes built after July 1, 1998

• If your home was built after 1st July 1998, the building regulations require that it is fitted with a standby radon sump. This is simple pipe work that extends from under the foundations into the outdoor air.
• For houses built in High Radon Areas the installation of a radon barrier as well as a standby sump is required.
• The installation of these protective measures is not a guarantee that radon concentrations will be below the recommended level. You should therefore have a radon measurement made within the first year of moving into your new home.
• Should elevated radon levels be present, the standby sump can be activated by adding a fan.
• Installing radon barriers and sumps at the time of construction greatly reduces the cost and the small disruption associated with remediation as the need to excavate beneath the house to install a sump is avoided.