A humid basement can be uncomfortable to hang out in and makes the perfect breeding ground for mold spores. Mold in the home can cause a variety of health problems, such as respiratory problems, asthma attacks and skin irritations. Several natural techniques can help dehumidify a basement without the use of harsh chemicals or energy-guzzling dehumidifiers.

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Opening windows to ventilate can help reduce humidty.

Ventilation

Ventilation allows moisture in the air and pollutants to leave the basement. Open doors and windows in the basement to help prevent condensation, and also install ventilation pipes for appliances in the basement, such as dryers and heaters. Give boxes and furniture a little bit of space from walls to increase ventilation on basement surfaces and decrease humidity. Fans can help get the airflow going to allow humid air to exit the basement.

Moisture Cleanup

Reduce wetness in the basement by cleaning up spills immediately. Do not store any wet items in the basement because they will increase the humidity of the room. Dry off condensation on windows, pipes, walls or any other surfaces as quickly as possible. You'll want to check for condensation underneath appliances such as sinks.

Leak and Condensation Control

Fix leaky pipes, windows, appliances and doors, which contribute to moisture in the basement. Reduce the amount of condensation on windows by increasing their temperature with insulation. Installing double-paned windows or applying a layer of plastic weather proofing film over windows during winter can help reduce condensation and basement humidity. Insulate other cold surfaces in the basement that attract condensation, like water pipes.

Outdoor Drainage

Naturally reduce humidity by improving drainage around the house. Verify that the ground around the building slopes outward and away from the basement to prevent rain runoff from collecting around the basement. Keep up with gutter maintenance, and ensure that gutters do not drain right next to basement windows or walls. North Dakota State University also suggests at least 6 inches of gravel beneath a cement basement floor to allow water to drain away from the basement.