How to Remediate High Radon Levels

You have had your home tested and the come back above the Environmental Protection Agency's action guideline of 4.0 pCi/L.  The EPA recommends that all homes with radon readings above their action level have a radon remediation system installed.

Installing a radon remediation system is not for your average do-it-yourselfer.  It is a difficult job and one best left to a professional installer.  There are several variables that a contractor will take into consideration when deciding what type of system to install in your home.  These include: how high the radon readings are, the size of the home, what type of basement / foundation the home is sitting on and costs.

The most common type of system is an active sub-slab suction or sub-slab depressurization system.  This system involves installing suction pipes inserted through the slab floor which connects up to a radon vent fan.  This will draw the radon up and out of the home.

If your home is built on a crawlspace, another effective method of reducing radon is to cover the earth floor with a high-density plastic sheet and then use a vent pipe and fan to draw the radon out from under the plastic.

Other ways of reducing radon are by sealing cracks and other openings in the foundation and creating more ventilation in the home by bringing more outdoor air in with a heat recovery ventilator.  Natural ventilation- opening doors and windows to increase air circulation- can also be effective at reducing radon levels but is suggested just as a temporary measure.

In new construction homes, radon cannot be tested until the home is completely built.  In these cases, the most cost effective way of dealing with potential radon issues is to build in radon resistant features rather than addressing radon problems after the fact.  The EPA recommends that all homes being built in Zone 1 of the country be built with radon reduction systems.  Zone 1 areas,  including  Middlesex and Worcester counties in Massachusetts, are areas that have  high radon potential.

Some of these methods include barriers to radon such as plastic sheeting under foundations and sealing and caulking foundations.  Using seamless ducts in basements and crawlspaces or sealing the ductwork to prevent radon from being drawn into the system.  Installing passive sub-slab depressurization systems - with a junction box in the attic- can reduce radon levels up to 50% and if the levels still test higher than the EPA's action level, it easy to have a qualified mitigator add a vent fan to an existing passive system.

Whatever system is used, a monitoring device and warning system that alerts the homeowner if the system is no longer working is a must.  If you are planning on any future remodeling, such as in the basement or attic, make sure to ask your contractor is doing so will void your warranty.  And don't forget to retest your home within 30 days of the installation.