Prefabrication
The most commonly cited definition is by Goodier and Gibb in 2007, which described the process of manufacturing and preassembly of a certain number of building components, modules, and elements before their shipment and installation on construction sites.
The conventional method of building a house is to transport bricks, timber, cement, sand, steel and construction aggregate, etc.
Against these advantages must be weighed the cost of transporting prefabricated sections and lifting them into position as they will usually be larger, more fragile and more difficult to handle than the materials and components of which they are made.
For example, it is claimed that the world's oldest known engineered roadway, the Sweet Track constructed in England around 3800 BC, employed prefabricated timber sections brought to the site rather than assembled on-site.
[citation needed] Sinhalese kings of ancient Sri Lanka have used prefabricated buildings technology to erect giant structures, which dates back as far as 2000 years, where some sections were prepared separately and then fitted together, specially in the Kingdom of Anuradhapura and Polonnaruwa.
After the great Lisbon earthquake of 1755, the Portuguese capital, especially the Baixa district, was rebuilt by using prefabrication on an unprecedented scale.
Under the guidance of Sebastião José de Carvalho e Melo, popularly known as the Marquis de Pombal, the most powerful royal minister of D. Jose I, a new Pombaline style of architecture and urban planning arose, which introduced early anti-seismic design features and innovative prefabricated construction methods, according to which large multistory buildings were entirely manufactured outside the city, transported in pieces and then assembled on site.
The process, which lasted into the nineteenth century, lodged the city's residents in safe new structures unheard-of before the quake.
Also in Portugal, the town of Vila Real de Santo António in the Algarve, founded on 30 December 1773, was quickly erected through the use of prefabricated materials en masse.
[2] The Crystal Palace, erected in London in 1851, was a highly visible example of iron and glass prefabricated construction; it was followed on a smaller scale by Oxford Rewley Road railway station.
Prefabrication of modular wall elements allows building of complex thermal insulation, window frame components, etc.
However, tradition often favors building by hand in many countries, and the image of prefab as a "cheap" method only slows its adoption.
However, current practice already allows the modifying the floor plan according to the customer's requirements and selecting the surfacing material, e.g. a personalized brick facade can be masoned even if the load-supporting elements are timber.
Examples of off-site fabrication are wall panels for homes, wooden truss bridge spans, airport control stations.
It is growing at an accelerated pace both in more established markets such as North America and Europe and in emerging economies such as the Asia-Pacific region (mainly China and India).
