Common causes of damp or wet basements

Common causes of damp or wet basements:

Improper surface drainage - usually a result of soil around house sloping towards the house, instead of away.

Solution: Add topsoil around house to provide a gentle slope away from house.

No eaves trough, or downspouts that dump water adjacent to foundation

Solution: Install eaves trough and extend downspouts 10 feet from house.

Leakage around basement windows - basement windows are typically below ground level. Water will run to the lowest point (your windows) and enter around the base of the window.

Solution: Install window wells to help keep water away from window areas. Properly installed window wells will also effectively drain water away water from window areas.

Cracks in foundation walls or basement floor will allow ground water to enter.

Solution: Small cracks (up to 1/4“) that do not appear to grow larger over time, can be patched and sealed with patching compounds available at building stores. Larger cracks are generally indicative of a more serious problem and will require professional assessment as to the cause.

Drainage tiles installed at base of foundation are broken or plugged. Older houses used drainage tiles made from clay to divert water away from foundations. Over time, the clay tiles crack, collapse and get plugged with soil.

Solution: Excavate completely around foundation and replace weeper drainage system. Definitely not a do-it-yourself job. Professional assistance is a must to correctly diagnose the problem and to recommend the best solution.

Fact ! All concrete foundations will crack. New concrete will shrink as it dries and produce small cracks. Settling of soil, nearby construction, bus and truck traffic, tree roots and groundwater pressure all put strains on foundations.

Fact ! Over 90% of basement leaks can be fixed by keeping surface water away from the foundation. A good soil slope away from the house and properly installed eaves trough are a must. Two low cost solutions to try before considering more extensive & expensive alternatives.

Fact ! Ventilation of basement will draw out damp, humid air. Open windows a crack, install a mechanical ventilator and install cold-air return furnace ducts in the basement. A mechanical ventilation system or HRV (Heat Recovery Ventilator) will help keep your whole home fresh and healthy.



This information is provided for your general interest and is not intended to be technically exhaustive. Please consult a professional inspector or contractor to obtain an assessment of your particular situation.

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