Damp Basement Solutions for Homeowners
Over 60 percent of homes have a damp basement. High humidity causes molds and mildew, damages furnishings, may damage the structure itself, and is hazardous to people’s health. A damp basement may buckle wood flooring on the first floor. Moist insulation does not work well and moist air is more costly to heat or air condition. A damp basement will increase your heating and air-conditioning bills.
That Damp Basement Feeling!
- If your basement just feels damp,
- if cardboard boxes placed on the floor get moist and moldy,
- if the concrete is all wet when you lift a rubber-backed carpet,
- if you smell musty odors, the telltale sign of molds,
- if you see efflorescence (“white powder”), the telltale sign of water seepage – then, you have a damp basement! And you’d better fix it before it causes serious damage.
Drying up Damp Basements
Divert rainwater from the foundation by proper grading, gutters, and downspout extensions. Seal all cracks and openings. Make sure that your clothes dryer is exhausted to the outside and the duct is not plugged up by lint. When finishing the basement, avoid trapping moisture behind plastic sheets, impermeable wall or flooring materials and/or provide ventilation for water vapor seeping through concrete.
Air-conditioning
It will remove some humidity but not enough. It shuts off when it reaches the target temperature regardless of humidity. Still, a full 30% of an air conditioner’s load is used to remove humidity. By reducing indoor air humidity, you will save on air conditioning bills.
Dehumidifier
The common solution. Power consumption $30-50/month. Be sure to keep it clean to avoid mold growth, which would defeat its purpose. It draws in 20 to 30% more moisture through the concrete, which in the long run speeds up its deterioration and allows in more moisture.
Air-to-air exchanger
Pulls out humid air from the basement and draws in fresh air from the outside. Unlike just openings the windows, the exchanger reduces the energy losses in heated or air-conditioned air. In general, a good solution for today’s “airtight homes” with low fresh air exchange. But rather costly initial cost and operation.
Sealing the basement
The most basic, least expensive, and most effective method. No on-going running costs. Seal the concrete walls and floor with Radon Seal and then, seal or caulk all openings, gaps, or cracks.