Carl Macgowan | Newsday

Mold is commonly found in single-family homes, but less is known about how prevalent it is in larger buildings, one expert said.

Studies have found that a third to half of single-family homes have evidence of mold, said William Fisk, a senior scientist at Lawrence Berkeley National Laboratory in Berkeley, Calif.

Data on mold in large buildings, though scant, suggest "it's significant problem," Fisk said.

It's rare for mold to lead to the evacuation of an entire complex, he said. "In many cases, mold contamination is remediated without shutting down the building," Fisk said.

Mold is usually the result of flooding, leaks from outside due to construction or maintenance problems, or groundwater, Fisk said.

What To Do If You Find Mold

  • Control the moisture problem - The source of the water that caused the mold must be identified and corrected.
  • Discard porous materials, such as drywall, carpeting, paper and ceiling tiles, with extensive mold growth.
  • Throughly dry all wet materials - If that is not possible, they should be discarded.
  • Clean mold growing on wood, concrete and other hard surfaces - SMall areas can be scrubbed with a rag soaked in diluted detergent. For a large mold problem or if you are highly sensitive to mold, an experienced professional should do the work.
  • Use a 10 percent bleach solution to treat the area and keep mold grown under control if it is impractical to eliminate the water source. In areas that can be kept dry, bleach is not necessary. Make sure there is plenty of fresh air to prevent eye, nose or throat irritation.
  • Monitor the area for new mold growth and signs of moisture. This may indicate the need for durther repairs or material removal.