How to Remove Moisture With a Migration System Under a Cellar Floor

Install and maintain rain gutters to keep moisture away from the cellar. To assist in drainage, make sure the gutters point away from the home at the bottom; if possible, install them over soil sloped away from the home to assist in drainage. Keep the gutters free of debris and obstruction to avoid clogs and backups.

Keep wood materials used in cellar construction that have not been treated for moisture resistance away from direct soil contact. This will prevent moisture in the soil from saturating the wood parts of your cellar and creating ideal conditions for mold and mildew growth that can rot the wood.

Install a vapor barrier, sometimes called a vapor diffusion retarder, underneath the cellar's slab floor. The most commonly used materials for this process are polyethylene film over at least 4 inches of gravel to act as a buffer between concrete and soil moisture.