are the main ways to control moisture in your home?
- The key to mold control is moisture control.
- If mold is a problem in your home, you should clean up
the mold promptly and fix the water problem.
- It is important to dry water-damaged areas and items
within 24-48 hours to prevent mold growth.
Water in your home can come from many sources. Water can enter your
home by leaking or by seeping through basement floors. Showers or even cooking
can add moisture to the air in your home. The
amount of moisture that the air in
your home can hold depends on the temperature of the air. As the temperature
goes down, the air is able to hold less moisture. This is why, in cold weather,
moisture condenses on cold surfaces (for example, 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, your options range from simple landscaping to extensive
excavation and waterproofing. (The ground should slope away from the
house.) Water in the basement can result from the lack of gutters or a
water flow 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 to prevent
moisture from coming in from the ground. Be sure crawlspaces are
- Use exhaust fans in bathrooms and kitchens to remove
moisture to the outside (not into the attic). Vent your clothes dryer to
- Turn off certain appliances (such as humidifiers or
kerosene heaters) if you notice moisture on windows and other surfaces.
- Use dehumidifiers and air conditioners, 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 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
- (plastic sheeting) over the concrete and cover that with
sub-flooring (insulation covered with plywood) to prevent a moisture
- 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 lead to different problems and solutions.
Your humidistat is set too high if excessive moisture collects on windows and
other cold surfaces. Excess humidity for a prolonged time can damage walls
especially when outdoor air temperatures are very low. Excess moisture condenses
on window glass because the glass is cold. Other sources of excess moisture
besides overuse of a humidifier may be long showers, running water for other
uses, boiling or steaming in cooking, plants, and drying clothes indoors. A
tight, energy efficient house holds more moisture inside; you may need to run a
kitchen or bath ventilating fan sometimes, or open a window briefly. Storm
windows and caulking around windows keep the interior glass warmer and reduce
condensation of moisture there.
Humidifiers are not recommended for
use in buildings without proper vapor barriers because of potential damage from
moisture buildup. Consult a building contractor to determine the adequacy of
the vapor barrier in your house. Use a humidity indicator to measure the
relative humidity in your house. The American Society of Heating and Air
Conditioning Engineers (ASHRAE) recommends these maximum indoor humidity
Recommended Indoor Temperature Relative Humidity