How Do I Prevent Mold Growth In My Home?

Food sources for mold are plentiful: wood construction materials, furniture, paper in drywall and wallpaper, organic fibers in fabrics, carpet backings, and dust. If these organic food sources are exposed to high levels of moisture in our homes, mold can grow.

The nose knows: Musty odors are a sign of mold growth in a building. Look for visible signs of mold and/or moisture, then eliminate the moisture source.

Humidity levels: Current recommendations from the NAHB suggest keeping maximum relative humidity levels below 40% during the heating season and below 60% during the cooling season.

Proper ventilation: Bathroom fans, kitchen fans, and clothes dryers should be vented to the outside of the building envelope (or home). Energy recovery ventilation is recommended in tightly constructed homes having less than 0.35 fresh air changes per hour.

Seal of approval: Sealing outlets, sill plates, and through-wall penetrations (including doors and windows) can minimize uncontrolled air infiltration. Insulating pipes and ductwork in humid spaces can minimize condensation in these areas. Vinyl wall coverings should not be applied to concrete walls because moisture can accumulate behind them. Slabs and crawl spaces should have a vapor retarder beneath them to prevent moisture from entering a home.

Inspection and maintenance: Regular inspection and cleaning of the condensation drain line on a central air conditioning unit is recommended. Inspect the roof, windows, and siding after storms to identify missing shingles, damaged flashing, and visible water leaks.

Are Concrete Homes Affected By Mold:

No, the concrete, foam, and steel in a concrete wall system are not a food source for mold growth unlike wood studs, joists, and wall sheathing. However, organic materials, such as floor decking, paper-faced drywall, and carpet, are used inside concrete homes. These products can support mold growth and should be treated accordingly. Regardless of the building system, there is no substitute for good construction practices, regular inspections, and preventative maintenance to keep mold from getting a foothold in your home.

What'S The Bottom Line:

Homeowners have a responsibility to regularly inspect and maintain the components of their home to ensure that water is not accumulating in the building. Preserve reasonable humidity levels and fresh air exchange rates. Evidence of mold or moisture (visibly or by smell) should be addressed immediately to locate and eliminate the moisture source. Affected materials should be thoroughly dried, or removed and replaced.

Portland Cement Association (PCA)
5420 Old Orchard Road,
Skokie, Illinois 60077-1083
Phone: 847.966.6200
Fax: 847.966.9281

More information: Helpline- 1.888.333.4840