Manufactured homes have many of the same problems in their crawl spaces as do stick built homes. These include standing water problems, poor drainage, contaminated or old ineffective insulation in the floor, mold and allergens and rodent infestation. Most manufactured homes do not have a standard crawl space in that very few are built on a foundation. Most are installed above ground and are supported by concrete pier blocks and/or concrete runners and tied down from there. Typically the perimeter of the home is surrounded by a skirt. The skirt provides a finished look to the home as well as a deterrent to rodents and other unwanted animals.