State University Extension
Home Maintenance And Repair - 01500038
1. Keep Things Clean
Keep closets, dresser drawers, basements--any place where mildew is
likely to grow--as clean as possible. Soil on dirty articles can supply
enough food for mildew to start growing when moisture and temperature
are right. Greasy films, such as those that form on kitchen walls, also
contain many nutrients for mildew-causing molds.
2. Get Rid of Dampness
Dampness in a basement, or any other structure, is often caused by
condensation of moisture from humid air onto cooler surfaces. Excessive
moisture may indicate that repairs or additional insulation are needed.
Replace cracked or
defective mortar. Some basements are continually wet from water leaking
through crevices in the wall. Make sure outside drainage is adequate.
3. Control Moisture
For waterproofing concrete and other masonry walls above ground, apply
two coats of cement paint, tinted with mineral coloring if desired.
Waterproofed coatings to seal absorbent brick and other outside
surfaces may be needed.
Spread a layer of moisture-barrier material over the soil in crawl
spaces under houses. You can use heavy roofing paper or polyethylene
plastic film. Good ventilation is important. If possible, do not
enclose the crawl space. In extreme cases, a fan or blower may be
needed to move the humid air from under the building.
Cooking, laundering, and bathing may add 2 gallons or more of water a
day to the house. If circulation is not adequate use some type of
exhaust fan. If your clothes dryer is equipped with a vent, have it
exhausted to the outside to remove moist air.
4. Dry the Air
Cool air holds less moisture than warm air. Properly installed
air-conditioning systems remove moisture from the air by taking up warm
air, cooling it (which removes the moisture) and circulating the cool
dry air back into the room. In rooms that are not
air-conditioned-especially the basement--mechanical dehumidifiers are
useful. A humidistat can be attached to the unit to control the
humidity. Mechanical dehumidifiers, however, can add heat to a room.
When using air-conditioners or dehumidifiers, keep windows and doors
Get rid of dampness by heating the house for a short time. Then open
doors and windows to let out the moisture-laden air. An exhaust fan may
be used to force it out.
Air in closets and other small areas can be dried by using an electric
light continuously (60- to 100-watt bulb). The heat will prevent mildew
if the space is not too large.
PRECAUTION: Be sure to place
the light bulb far enough from clothing and other flammables to avoid
the danger of fire.
Chemicals that absorb moisture--may be used to absorb moisture from the
air. Follow directions on the label exactly.
6. Circulate the Air
When the air outside is drier than that inside, ventilation allows the
dry air to enter, take up excess moisture, and then be carried outside.
When natural breezes are not sufficient, you can use electric fans
placed in a window, set in a wall, or ducted to the attic to move air
from the house.
Poorly ventilated closets get damp and musty during continued wet
weather, and articles stored in them are apt to mildew. Try to improve
the air circulation by opening the closet doors or by installing a fan.
In addition, hang the clothes loosely so that air can circulate around
them. Dry all wet clothing (including clothes wet from rain or
perspiration) before putting it in the closet.
7. Get Rid of Musty Odors
Get rid of musty odors as soon as possible to prevent further mold
growth. Usually musty odors disappear if the area is well heated and
dried. If the odors remain, the following treatment may be necessary.
On cement floors and on tiled walls and floors in bathrooms, get rid of
mustiness by scrubbing with a diluted solution of sodium hypochlorite
or other chlorine bleach available in grocery stores. Use one-half to 1
cup of liquid household bleach to a gallon of water. Rinse with clear
water and wipe as dry as possible. Keep windows open until walls and
floors are thoroughly dry.
PRECAUTION: Work quickly and
carefully on plastic and asphalt tile to avoid spotting the surface.
This article was written by Anne Field, Extension Specialist, Emeritus,
with reference from the USDA bulletin, Mildew.
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status. Issued in furtherance of MSU Extension work, acts of May 8 and
June 30, 1914, in cooperation with the U.S. Department of Agriculture.
Thomas G. Coon, Director, MSU Extension, East Lansing,MI 48824. This
information is for educational purposes only. Reference to commercial
products or trade names does not imply endorsement by MSU Extension or
bias against those not mentioned.
information.was reviewed as
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