Mold growth is a dangerous condition in any home or building that can result in health hazards if you do not remove it quickly. One area where mold often goes unnoticed is underneath carpeting or other flooring materials. When the flooring is removed, mold is then found growing on the wooden subfloor. Before you reinstall new flooring, you must thoroughly clean and disinfect the wooden subfloor to prevent the spores from spreading into the home.

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Moldy subfloors must be cleaned before you install flooring.

Step 1

Put on safety glasses, disposable rubber gloves and a respirator before attempting to remove the mold. Individual mold spores are not visible to the eye and are harmful if inhaled.

Step 2

Fill a handheld sprayer with water and spray a fine mist of water over all moldy areas of the subfloor until they are barely damp. This prevents the spores from detaching and becoming airborne.

Step 3

Fill a large bucket with water and a detergent that does not contain ammonia using the proportions indicated on the detergent bottle. Insert a long-handled scrub brush into the mixture and use it to scrub the surface of the subfloor.

Step 4

Rinse the bush often and empty the bucket multiple times during the cleaning process to eliminate mold spores. Continue scrubbing the entire subfloor.

Step 5

Fill a fresh bucket with a mixture of 1 1/2 cups of bleach and 1 gallon of water. Mop the solution onto the subfloor using the brush to kill any remaining spores. Reapply the mixture as need for 15 minutes to prevent the floor from drying.

Step 6

Empty the bucket and refill it with clean water. Rinse the entire floor using the scrub brush and dipping it frequently into the clean water bucket.

Step 7

Plug in fans and a dehumidifier and place them in the room to remove the moisture from the floor and air as quickly as possible. Check the dehumidifier once per hour and empty the tank if it gets too full.