Exterior walls and the marriage line in a double wide are examples of load bearing walls in prefabricated homes. Load-bearing walls are often the exterior walls and walls along a double wide's marriage line. These walls usually consist of concrete or brick and are the structures that protect other parts of the home by taking pressure off of them. The weight of a manufactured home is transmitted through its foundation to the ground. The structure's foundation must be designed to support this load. There are two types of foundations for mobile homes: full and partial. With a full foundation, the ground beneath the home is excavated to a depth sufficient to accommodate the height of the home with space left over. The excess soil is removed and the area leveled off. A house trailer park will usually have full foundations because they can take several trailers at a time. If you plan to move your mobile home later on or sell it, a full foundation makes it easier to do so. Full foundations can also be seen as an improvement option if you need more room to build a garage, shed, or patio. A partial foundation is only deep enough to cover the floor joists on which the home rests. The home may be raised above ground level on posts set into the ground. Or, it may sit on blocks that are placed under the floorboards of the trailer.