Basement mold and mildew grows in moist conditions.

How to Remove Basement Mold & Mildew Safely

by Merle Huerta

Basement mold and mildew grows in moist, poorly ventilated conditions. Cleaning the mold and mildew is critical; long-term exposure can cause asthma and allergic sensitivity. It also damages property and impacts property value. To clean basement mold and mildew, the Environmental Protection Agency recommends a biocide, or a detergent that kills mold and mildew.


Locate the moisture source. Repair any plumbing leaks. If the home is built in a flood zone, consider more permanent solutions to prevent water from seeping into the basement.

Wear protective clothing including non-venting goggles, an N-95 respirator, and rubber gloves.

Open doors and windows to increase air circulation to the basement.

Clean mold and mildewed surfaces by scrubbing wood and concrete surfaces with a mild alkaline solution of a half-cup of washing soda to each gallon of water. Other detergents such as trisodium phosphate are sold in hardware stores.

Rinse wood and concrete surfaces with clean water. Allow to dry completely.

Eliminate musty odors by scrubbing basement floors with a solution of one cup of bleach to each gallon of water. Rinse well with clear water.

Run fans in the basement to circulate air. To prevent further mold growth, all surfaces must dry completely.

Reduce indoor humidity by installing a dehumidifier. Once the basement is dry, run the dehumidifier with windows and doors closed.

Place a container of silica gel, cat litter, anhydrous calcium sulfate, or other compound that absorbs moisture in the basement.

Items you will need

  • N-95 respirator
  • Rubber gloves
  • Disinfectant detergent
  • Bleach
  • Scrub brush
  • Goggles
  • Fans


  • If mold and mildew covers more than 10 square feet of a basement, the Environmental Protection Agency recommends professional treatment.


  • If a home is built in a flood zone or has a persistent leak, have the water problem evaluated by a professional. Mold and mildew will return if the water problem isn't fixed.
  • Always remove a vacuum cleaner bag outside the home if it has been used to vacuum mold. Do not re-use a bag used to clean basement mold and mildew.

About the Author

Merle Huerta, an adjunct instructor of English skills, began writing during her husband's combat deployment to Iraq in 2003. Her articles have appeared in "The Jerusalem Post," and USA Travel Tips, among other publications. Huerta has an M.A. in instructional media and technology from Columbia University and is a graduate of CUNY's The Writers Institute.

Photo Credits

  • Jupiterimages/ Images