Mold 5. Avoidance

Control moisture and keep materials dry to avoid mold problems.

TO FIND HUMIDITY & MOISTURE PROBLEMS:

Watch for condensation on windows, especially if on double-glass.
Use a relative humidity meter (hygrometer) to see if you have excess humidity.
Use a moisture meter to find damp spots in ceilings, walls, floors.
Look for wet or stained surfaces, under basement carpets, or behind baseboards.
Sniff for moldy or damp odors near carpets, or in air leaking in through cracks.

TO REDUCE MOISTURE CONDENSATION:

Avoid condensation that forms when warm, moist air contacts a cold surface, by:

Open windows for fresh air to enter, especially bedrooms overnight.
Increase attic and crawl space ventilation: uncover blocked vents.
Vent exhaust fans and clothes dryers to outdoors (not into attic or crawl spaces).
Use exhaust fans when showering (and after), steaming, or cooking with gas.
Wire fans to run more often with a shut-off timer switch, with the light switch, best with a dehumidistat, or continuously (can be smaller and quieter).
Connect clothes dryer exhaust vent securely to outdoors; keep vents clean.
Install filtered fresh air entry vents in downstairs closets for makeup air to enter from outdoors when exhaust fans operate, instead of up through the floor.
Keep furniture and clothing a few inches away from exterior walls.
Run a dehumidifier in the dampest problem areas, like basements.

TO STOP MOISTURE PROBLEMS:

Find and stop any leaks from plumbing, rainwater, or groundwater.
Dry and clean up after any flooding or leaks.
Waterproof bathtub/shower tile grout, building envelope, and concrete below grade.

TO IMPROVE DRAINAGE:

TO AVOID MOLD GROWTH:

Wipe condensation from windows, and ventilate more.
Dry or replace water-damaged carpets and building materials quickly.
Dry all cellulose products (paper, cardboard, wallpaper, ceiling tiles, wood, carpeting) indoors, and remove such debris from the crawl space.
Clean cooling coils and condensate drain pans in air conditioners, dehumidifiers, and refrigerators annually.
Do not use a humidifier (moisture helps mold grow).
Clean any salt “efflorescence” from masonry to help it dry.
Remove carpets, and cover concrete floors with a vapor barrier of paint, plastic sheet, or vinyl flooring, then perhaps finish flooring.
Avoid unglazed clay pots. Replace the top inch of soil annually.

TO AVOID MOLD IN A BASEMENT:

Add a pint of water, then 1/4 cup of mineral oil to basement floor drains annually.
Waterproof, ventilate, and heat the basement before finishing it below ground level.
Operate a dehumidifier if needed to keep humidity below 60%.
Raise stored items off a concrete floor.
Avoid placing objects that block air flow near concrete or damp walls.

TO AVOID MOLD IN A CRAWL SPACE:

TO CONTROL AIRBORNE MOLD:

To control mold and other fine dust particles that are indoors:

Vacuum clean carpets often, with ventilation/filtration running or windows open.
Use washable floor mats or rugs in entryways and other traffic areas.
Filter dust particles out of the air, especially when there is much activity.
Use high efficiency pleated filters that fit well in the furnace cold air return.
Switch the thermostat to get continuous air flow often, even when not heating.
Use portable air cleaners with good filters in areas where you spend much time.

===