- 1). Open the vents periodically if your crawlspace has them. Open them especially after a it rains. This allows air to flow in and out of the crawlspace while it dries out.
- 2). Remove moisture by placing dehumidifiers in the crawlspace. The dehumidifiers help eliminate any moisture, which can lead to a musty smell as well as mold and mildew in the crawlspace. If a dehumidifier cannot be placed in the crawlspace, use fans to pull moist air from the crawlspace through opened vents.
- 3). Dirt floors should be covered in crawlspaces with 6 mil polyethylene, available at many hardware stores. The sheeting should overlap the walls by a foot or more. Follow the manufacturer's instructions for installing the sheeting.
- 4). Seal all joints and cracks in the crawlspace's foundation and walls with elastomeric caulk. Elastomeric caulk has more stretch than traditional caulks. The increase elasticity allows it to shift with the house, which prevents cracks from growing. Follow the manufacturer's directions when applying the caulk.
- 5). Cover all vents with vent covers. These screens keep out any unwanted animals, and are available at many hardware stores.
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