Moisture and soil gases can be eliminated by specific construction techniques and materials. Often a special mastic coating and drain board is applied to the exterior of the foundation wall. At the foundation footing, drain tile is installed so that the water will run down the drain board and drain away from the house.

Gravel fill is used beneath the foundation slab with a poly membrane, or vapor retardant, sealed over the gravel prior to pouring the basement floor. The poly is sealed at the edges and seams preventing moisture, radon and other soil gases from migrating into the home.

-- Tips courtesy of HomeAdvisor.com