Check your home-humidity level with a hygrometer. You may also determine whether your humidity level is too high by observing floors and windows; if your windows have frost or condensation during the winter or if your wood floorboards separate, you need to reduce humidity.
Turn on bathroom and kitchen exhaust fans when bathing, showering or cooking to eliminate excess moisture.
Install and use air conditioning or ceiling fans to circulate air. If using central air conditioning, install a vent in the most humid part of the home.
Check your faucets, toilets and pipes for leaks and repair any that you find.
Inspect the gutters and rain spouts around your home. Clear out debris to prevent water from pooling up, and position the spout openings away from your foundation.
Inspect the soil around your home. It should slope away from your home, allowing water to drain away from the foundation. Avoid overwatering grass and plants.
Run a dehumidifier in humid parts of the home and empty the water tray on a daily basis.
Reduce water vapor by decreasing bath and shower times, watching your cooking to prevent excess boiling and using the washing machine sparingly.