Buildings Constructed after July 1998
Under the 1997 Building Regulations (Technical Guidance Document (TGD) – C) all new buildings constructed after July 1998 should have Radon protection measures installed.
> In High Radon Areas, a Radon barrier membrane and standby sump with pipework terminating in the footpath should have been installed.
Radon Testing.ie recommends that all newer Buildings constructed in High Radon Areas after July 1998 be tested. There is no guarantee that radon concentrations will be below the recommended level as it is extremely difficult to achieve an 100% gas tight Radon barrier under building site conditions. If the levels of Radon are found to be high then standby Radon sump can be activated (passive or active).
> In areas other than High Radon Areas, a standby sump with pipework should have been installed (Areas shown on Radon Map).
Radon Testing.ie recommends that all newer buildings constructed in areas other than High Radon Areas after July 1998 be tested, as there is no guarantee that radon concentrations will be below the recommended level (High readings have been recorded in these areas). If the levels of Radon are found to be high then standby Radon sump can be activated (passive or active).
Buildings Constructed before July 1998
These buildings would not have Radon protection measures installed and Radon Testing.ie advise that these buildings should be tested. If the levels of Radon are found to be high then a Radon sump can be installed.
The sump can be formed either internally or externally in the building. There is less disruption with the external method. A bucket size space is formed under the ground floor of the building in the hardcore fill. Then a duct pipe is fitted to the sump and seal. This pipe run either internally in the building exiting through the roof or externally fixed to a wall rising above the eaves.
- The sump and pipe can be used as a passive system (The system uses the stack effect to draw the Radon from under the building). It may be suitable for levels up to 400(Bq/m3). Following a re-test if the levels were found to be still high, a fan can be fitted. It then becomes an active system.
- When a small electric fan is fitted to the sump it is called an active system. This is the preferred method and gives the most effective solution for the removal of the Radon risk. It has been found to be effective for levels of above 2000 (Bq/m3).It is recommended that a sump be installed for every 250m2 of ground floor area. Sumps can be linked to a single Fan.