Examine the overall condition of the crawl space before you begin cleaning. Check for mold, mildew and moisture, which can leave an odor, cause structural damage and health problems, and require additional cleaning supplies and repair materials.Remove any items stored in the crawl space, clean and store items in a different location in the home.Crawl spaces should not be used for storage because moisture can permeate the surface of items and create a breeding ground for mold and mildew.heck for mold, mildew and moisture, which can leave an odor, cause structural damage and health problems, and require additional cleaning supplies and repair materials. Remove any items stored in the crawl space, clean and store items in a different location in the home.