Claudette Reichel, Merrill, Thomas A. | 6/10/2005 12:33:35 AM
When storms start to approach, one question some people have to ask is how do I prevent mold if my home floods?
With Hurricane Lili threatening Louisiana this week, LSU AgCenter housing specialist Dr. Claudette Reichel says it’s important to keep in mind that mold results from lingering moisture.
"If you prevent materials from staying wet for longer than two or three days, you prevent mold problems," Reichel advises, stressing, "So your key objective and priority should be ‘speed drying,’ rather than bleaching everything or testing for mold."
Reichel says disinfectants such as bleach kill molds but that dead mold spores in the air are just as unhealthy as live spores – so disinfectants must be used with care to avoid harm to people and materials. She also says air sampling for mold can be expensive and difficult to interpret, so it’s always best to prevent mold from growing in the first place.
"If mold does develop, fixing the problem quickly is needed no matter what type of mold is found, so investing in solving the moisture problem should be a top priority followed by looking for and cleaning away visible mold as soon as it appears," Reichel advises.
The LSU AgCenter specialist offers these tips for preventing mold growth after flooding:
–Remove wet carpeting right away. It’s best to discard it, but if you try to salvage carpet, you should clean it, disinfect it and dry it quickly with professional equipment and specialized solutions. Work outdoors if possible. And never reuse flooded padding.
–Cut away wet wallboard and remove all wet and damp insulation right away, even if wallboard appears to be dry. Wet insulation will stay wet far too long, leading to the growth of hidden unhealthy mold and decay fungi inside the walls.
–Clean with non-phosphate detergents (any phosphate residue is mold food). If you disinfect, follow directions carefully and never mix bleach with ammonia or acids (vinegar). Disinfectants can kill molds, but they do not prevent re-growth.
–Do whatever you can to speed the drying of subfloors, slabs and wall framing before replacing insulation, wallboard and flooring. Use air conditioning or heaters, fans, or, better yet, a dehumidifier. Professional water damage restoration contractors with special equipment (dehumidifying blowers) can provide the fastest drying.
–Test the moisture content of studs and sheathing (using a moisture detector) before replacing insulation. Wood should drop below 20 percent moisture content by weight before you close the wall.
–Do not install vinyl wallpaper on walls. That would prevent further drying of what’s inside the wall.
–Make sure the slab is dry before replacing sheet vinyl or glued wood flooring. Ceramic tile’s grout and floating plank wood flooring allow drying, so it can be installed sooner.
As for talk of "toxic molds" that have been in the news lately, Reichel explains any mold actually can pose health problems – although one of them is getting a lot of attention.
"There are many types of molds. In the right conditions, they multiply and can release enough spores in the air to cause health problems - especially for those with asthma, allergies, illnesses and other susceptibilities," she says, adding, "Some people are much more sensitive to mold than others."
The LSU AgCenter specialist says all molds are considered a health hazard, but some types also produce various mycotoxins that are carried in the spores.
"Health effects vary widely and are difficult to isolate in a clear cause and effect relationship," she says. "Some of the possible effects indicated by scientists include asthma, allergic reactions, suppression of the immune system, various lung problems and possible neurological effects."
Reichel says the mold in the news a lot lately is stachybotrys chartarum.
"It is not your common mildew. It is a greenish black, slimy mold that grows on cellulose material (wood, paper, etc.) that has been saturated for a long time - generally from flooding or leaks," she says. "It is not the only indoor mold that produces mycotoxins, but it has gotten a lot of attention because of suspected relationships with some serious effects."
To get more information from LSU AgCenter experts, visit www.LouisianaFloods.org for information about restoring your flooded home and protecting your home from future flood damage. Visit www.LouisianaHouse.org for information on home and landscape improvements to make your home safer, stronger and smarter. Or visit www.lsuagcenter.com for access to those sites and a variety of other helpful information.
Free information about mold clean-up and additional resources are available from the EPA Indoor Air Information Clearinghouse online at www.epa.gov/iaq or by phone at (800) 438-4318.