How to Prevent Mildew in Crawl Spaces
- 1). Ensure that there is no water coming into the crawl space. Examine the crawl space for water after a rainstorm. Check for cracks in the walls of the foundation and breaks or blocks in gutters and drainage pipes. Make any necessary repairs to prevent moisture in the crawl space.
- 2). Coat the walls of the crawl space with water-resistant paint. Also consider using a mildew-resistant paint.
- 3). Prevent moisture in crawl spaces by covering the soil with a material that will prevent the buildup of moisture, such as a polyethylene plastic film.
- 4). Keep the crawl space ventilated. Open any foundation vents to allow cross-ventilation. If there are no vents, use a fan or leaf blower to force humid air out of the space. Protect your eyes with goggles and wear a mask to avoid inhaling the dust.
- 5). Place a chemical in the crawlspace that absorbs moisture from the air. These include anhydrous calcium chloride, silica gel and activated alumina. Pour the chemicals onto several trays, place the trays around the crawl space and leave them for about two weeks. As the chemicals absorb the moisture, they begin to change in appearance. For instance, silica gel granules are originally colorless but will become pink when saturated with water; and anhydrous calcium chloride liquefies when it is full of water.
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