Prefabricated homes, often referred to as prefab homes or simply prefabs, are specialist dwelling types of prefabricated building, which are manufactured off-site in advance, usually in standard sections that can be easily shipped and assembled. Some current prefab home designs include architectural details inspired by postmodernism or futurist architecture.
The word ‘prefab’ is not an industry term like modular home, manufactured home, panelized home or site-built home. The term is an amalgamation of panelized and modular building systems, and can mean either one. In today's usage the term ‘prefab’ is more closely related to the style of home, usually modernist, rather than to a particular method of home construction.
‘Prefabricated’ may refer to buildings built in components (e.g. panels), modules (modular homes) or transportable sections (manufactured homes), and may also be used to refer to mobile homes, i.e., houses on wheels. Although similar, the methods and design of the three vary widely. There are two-level home plans, as well as custom home plans. There are considerable differences in the construction types. In the U.S., mobile and manufactured houses are constructed in accordance with HUD building codes, while modular houses are constructed in accordance with the IBC (International Building Code).
Mobile homes and manufactured homes can be placed in mobile home parks, and manufactured homes can also be placed on private land, unless the land is within a subdivision whose CC&Rs prohibit manufactured housing.
Constructing manufactured homes typically involves connecting plumbing and electrical lines across the sections, and sealing the sections together. Manufactured homes can be single, double or triple-wide, describing how many sections wide it is. Many manufactured home companies manufacture a variety of different designs, and many of the floorplans are available online. Manufactured homes can be built onto a permanent foundation, and if designed correctly, can be difficult to distinguish from a stick-built home to the untrained eye.