The rain could hit clogged gutters and back up under the eaves and drip into the home, said Dr. Dennis Ownby, chief of allergy and immunology at Georgia Health Sciences University.
“If people have had a small leak in a roof that they haven’t gotten around to fixing or don’t know about, with all of this extra rain, suddenly a very tiny problem may become a significant problem because of the amount of water getting into the house,” he said.
Or it could be structural, Ownby said.
“So many of our homes here in the South are built on crawl spaces,” he said. “If water gets under the crawl space and sits, that creates a huge amount of humidity and mold in the house. That’s a potential big problem, especially when we go for days with very humid weather and a lot of rain.”
The problem could then result in mold. In its authoritative 2004 review, titled Damp Indoor Spaces and Health, the Institute of Medicine concluded there was enough evidence to show an association with wheezing, exacerbating asthma symptoms in those with asthma, and nose and throat problems. But there was too little definitive research on the actual irritants and what levels would cause a problem indoors. It called for more research, which unfortunately hasn’t happened, Ownby said.
“We know that some people are clearly allergic to the molds and the spores that they give off,” he said. “Other molds do produce a whole variety of toxins. There’s not a lot of information about what the effects of those toxins are, (or) the kind of levels that may be present in a home.”
A certain toxic mold called Stachybotrys chartarum was suspected in several deaths in children in Cleveland in the 1990s but there were other air pollutants in the homes, including cigarette smoke, that meant no firm conclusions could be drawn, Ownby said.
Visible mold is clearly a sign of a moisture problem but others might not be so obvious, said Dan Troutman, the president of Alternative Construction & Environmental Solutions in Augusta, who gets called in to do mold assessment and cleanup.
“It can be growing in a wall, it can be growing in areas behind paint, behind wall coverings, that are not visible to the naked eye at first,” he said.
The problem doesn’t have to be just allergies, Troutman said.
“The mold spore itself can be a physical irritant,” he said, comparing it to a grain of sand.
Best thing to do is, once the rains stop, make sure any damp places or water pooling in the crawl space is addressed, Ownby said.
“People need to be aware of it and not put it off,” he said.