Prefabricated home

Construction of a prefabricated modular house (Click here for a time-lapse video)

Prefabricated homes, often referred to as prefab homes, 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.

Word origin

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 panellized 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 Housing

Uninhabited prefabricated council houses in Seacroft, Leeds, UK

"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 wildly. There are two-level home plans, as well as custom home plans. There are considerable differences in the construction types. Mobile and manufactured houses are constructed in accordance with the HUD building codes^[jargon] in the U.S. while modular houses are constructed in accordance with the IBC (International Building Code).

• Modular homes are created in sections, and then transported to the home site for construction and installation. These are typically installed and treated like a regular house, for financing, appraisal and construction purposes, and are usually the most expensive of the three. Although the sections of the house are prefabricated, the sections, or modules, are put together at the construction much like a typical home. Manufactured and mobile houses are rated as personal property and depreciate over time.
• Manufactured homes are built onto steel beams, and are transported in complete sections to the home site, where they are assembled.
• Mobile homes built on wheels, that can be moved.

Mobile homes and manufactured homes can be placed in mobile home parks, and manufactured homes can also be placed on private land, providing the land is zoned for manufactured homes.

Manufactured homes

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.^{[citation needed]}

Manufactured homes are typically purchased from a retail sales company, initially assembled by a local contracting company, and follow-up repairs performed by the manufactured home company under warranty.

A manufactured home, once assembled, goes through a "settling-in" period, where the home will settle into its location. During this period, some drywall cracking may appear, and any incorrectly installed appliances, wiring, or plumbing should be repaired, hopefully under warranty. If not covered under warranty, the costs will be borne by the consumer. For this reason, it is important that the consumer ensure that a reputable and honest contractor is used for the initial set-up. If any repairs are not completed by the initial set-up crew, the manufacturer will send repair crews to repair anything covered by the warranty. The secondary repair team must be scheduled, and may not be available immediately for most repairs. Just because a manufactured home has been assembled does not mean it is immediately inhabitable; appropriate ventilation, heating, plumbing, and electrical systems must be installed by a set-up crew, otherwise, the buyer must wait for the manufacturer repair team or do it themselves.

North America

History

Wooden homes have always been popular in North America, due to the large quantities of timber available. In the United States, several companies began offering mail order kit homes between 1902 and 1910, among them Sears Catalog Homes.^[1] In the UK, more than 156,000 prefabricated homes were built between 1945 and 1948.^[2] After World War II until 1948, Sell-Fertighaus GmbH built over 5000 prefabricated houses in Germany for members of the occupying force of the United States of America.^{[citation needed]}

United States

A Modern North American log style prefabricated house

The prefab home or house requires much less labour as compared to conventional houses or homes. Most of the companies are selling complete pre-manufactured prefab modular homes or houses called "mobile homes" or "manufactured homes".

Local building codes in North America typically do not apply to prefab homes or houses; instead, these houses are built according to specialized guidelines (Federal HUD regulations, or their Canadian equivalents) for manufactured housing.

Zoning issues

Manufactured homes are not permitted in some communities and therefore, one should check from their local city to find about prefab building and construction laws regarding prefab homes before considering purchase.

Europe

German-manufactured Huf Haus near West Linton, Scotland

There is no pan-EU housing standard for this kind of home construction, as regulation has historically been at the national government level. There are however many EU directives that do apply to housing construction and design, but these directives do not directly affect the inter-EU modular home sector due to inter-EU free trade considerations. However, each modular home is legally expected or obliged to be integrated into the local building regulations once the final construction is finished.

United Kingdom

A post-WW2 English prefabricated house, adjoining a similar property reconstructed in brick

In the United Kingdom the word "prefab" is often associated with a specific type of prefabricated house built in large numbers after the Second World War,^[3] such as Airey houses, as a temporary replacement for housing that had been destroyed by bombs, particularly in London.

Despite the intention that these dwellings would be a strictly temporary measure, many remained inhabited for years and even decades after the end of the war. A small number are still in use in the 21st Century, but more and more are being demolished. In 2011 it was announced that Britain's largest remaining prefab estate of 187 homes in Lewisham, South-East London, is to be redeveloped except for six homes.^[4]

Australia/Asia

An Australian prefabricated house

There are a small number of prefab home builders in Australia/Asia. In the overall housing sector, prefab housing construction is very small as the overall rate of housing construction has been very low due to slow population growth.

The prefab sector in Australia/Asia is more optimised for exporting its product, as domestic consumption is limited.

In 2010, Bali exported 98,417 units of Prefabicated house, but in 2011 plunged to 5,007 units due to the global economic slowdown that affected a number of export destinations. The Balinese prefab houses are well known as its artistic and practical values.^[5]

Current market state

Prefab homes are becoming popular in Europe, Canada and United States as they are relatively cheap when compared to many existing homes on the market. The 2007 finance crisis has however deflated the cost of housing in North America and Europe, so not all prefab homes should be assumed to be cheaper than existing housing.

Modern architects are experimenting with prefabrication as a means to deliver well-designed and mass-produced modern homes. Modern architecture forgoes referential decoration and instead features clean lines and open floor plans.

Because of the design simplifications modern architecture provides (coupled with the cost savings that tend go with design simplification) many in the manufactured housing sector generally feel that modern architecture designs are better suited for prefab home construction.

See also

• Prefabricated building

References

External links

• National Association of Home Builders (US) - "NAHB's Building Systems Council's Concrete, Log, Modular, and Panelized Homes
• "Out & about: architecture: Prefab sproutings" by Jonathan Glancey in Guardian Unlimited, Wednesday August 31, 2005, accessed 12 October 2007
• From Africa to Queens Waterfront, a Modernist Gem for Sale to the Highest Bidder by William Hamilton in the NY Times on 1950s French modernist prefab built for Africa