Water comes into your home from many sources. Water enters your home by leaking or seeping through basement floors. Showers and cooking add moisture to the air in your home.
The amount of moisture the air in your home can hold depends on the temperature of the air. As the temperature goes down, air is able to hold less moisture.
That is why, in cold weather, moisture condenses on cold surfaces (drops of water form on the inside of a window.) This moisture can encourage biological pollutants to grow.
There are many ways to control moisture in your home:
- Fix leaks and seepage. If water is entering the house from the outside, options range from simple landscaping to extensive excavation and waterproofing. The ground should slope away from the house. Water in the basement results from not having gutters or from water flowing toward the house. Water leaks in pipes or around tubs and sinks can provide a place for biological pollutants to grow.
- Put a plastic cover over dirt in crawlspaces. This prevents moisture from coming in from the ground and be sure crawlspaces are well-ventilated.
- Use exhaust fans in bathrooms and kitchens. It removes moisture to the outside (not the attic) and vent your clothes dryer to the outside.
- Turn off certain appliances. If you notice moisture on windows and other surfaces turn off humidifiers and kerosene heaters.
- Use dehumidifiers and air conditioners. This is important, especially in hot, humid climates, to reduce moisture in the air, but, be sure that the appliances themselves don't become sources of biological pollutants.
- Raise the temperature of cold surfaces where moisture condenses. Use insulation or storm windows. A storm window installed on the inside works better than one installed on the outside. Open doors between rooms (especially doors to closets which may be colder than the rooms) to increase circulation. Circulation carries heat to the cold surfaces. Increase air circulation by using fans and by moving furniture away from wall corners to promote air and heat circulation. Be sure that your house has a source of fresh air and can expel excessive moisture from the home.
- Pay special attention to carpet on concrete floors. Carpet can absorb moisture and serve as a place for biological pollutants to grow. Use area rugs which can be taken up and washed often. In certain climates, if carpet is to be installed over a concrete floor, it may be necessary to use a vapor barrier (plastic sheeting) over the concrete and cover that with sub-flooring (insulation covered with plywood) to prevent a moisture problem.
Moisture problems and their solutions differ from one climate to another. The Northeast is cold and wet; the Southwest is hot and dry; the South is hot and wet; and the Western Mountain states are cold and dry. All of these regions can have moisture problems.
For example, evaporative coolers used in the Southwest can encourage the growth of biological pollutants. In other hot regions, the use of air conditioners which cool the air too quickly may prevent the air conditioners from running long enough to remove excess moisture from the air.
The types of construction and weatherization for the different climates can also lead to different problems and solutions.