Carla, Radon is a gas that is coming up through the ground. To remove the gas effectively, you must catch the gas with some type of barrier. A double layer of 6 of 10 mil poly the is sealed at the seams and sealed al the foundation walls. The sheet are install 90 across from each other. In many cases small gravel is placed on the sheeting to hold it in place. A radon mitigation pump (fan) is then selaed to the poly cover such that it can pull gas from under the poly sheeting. In order to pull a slight vacuum under the sheeting, a 4" pvc pipe is rum along the ground and under the sheeting. The pipe has 3/4" holes drilled at random points throughout the pipe and is attached to the Radon Pump.
