Credit: Photo by Pasi Aalto
Prefab designs: Made in Asia, for Asia
The modern history of prefabs is steeped in the architectural traditions of the West. From the reconstruction of post-war Britain to the housing shortages of America's industrial cities, factory-built homes were used to meet Western needs. These so-called "modular" buildings have, in turn, taken Western forms, their styles intertwined with architectural schools like modernism and the Bauhaus movement.
1/13 – Mulan Weichang Vistor Centre, Hebei, China by HDD
Yet, in the 21st century, it is perhaps Asia that will benefit the most from prefabs. The continent is now home to some of the highest rates of population growth and urbanization. The Asia-Pacific region is set to overtake the US as the world's largest prefabricated building market, with a projected growth rate of almost 6% a year between now and 2023, according to a recent report by Market Research Future.
Whether used for low-cost homes, disaster relief or temporary lodgings, modular homes are being adapted to Asian needs. In downtown Beijing, for example, the design firm People's Architecture Office (PAO) is using prefabrication to overcome challenges specific to the area's alleyways, or hutongs.
The firm's Plugin House project was designed in direct response to soaring land prices, planning restrictions and aging infrastructure in Beijing's historic Dashilar neighborhood.
"Beijing is one of the most expensive cities to live in," said PAO co-founder, James Shen, in a phone interview.
"But we found that about half the properties (in the neighborhood) were vacant. It turned out that the conditions were poor, and it was very difficult for people to upgrade them, for a variety of reasons -- it would disturb the neighbors, it would be expensive or there would be issues of historic preservation."
While the benefits of prefabs are often related to the reduced costs of mass production, for Shen it was about specific urban challenges. Each Plugin House is adapted to individual requirements, with many of them designed as extensions to traditional courtyard homes. Slotting between old, closely-packed structures, the units can improve quality of life for hutong residents by increasing living space, or offering insulation and private toilets in an area where many rely on public facilities.
After being produced in factory, the light prefabricated panels can be easily transported to the site through Beijing's narrow lanes. The homes are constructed without nails, tools or skilled labor, according to Shen.
"If people are relocated by construction, then (upgrading your home) can be very disruptive," he said. "But the Plugin House itself takes about a day to put up. This is really important when you're in hutong areas, because they're so dense -- and houses are so close to each other -- that you just can't disturb people too much."
Improving living conditions
In some circumstances, demand for modular housing is more immediate. For Asia's low-income communities, prefabs can offer affordable housing, while protecting them against natural disasters and challenging environments.
For VTN Architects, the firm founded by renowned Vietnamese architect Vo Trong Nghia, affordability and security both served as motivations. The practice's prefab series, S House, was specifically designed to address local needs, according to Nobuhiro Inudoh, one of a team of architects who worked on the prototypes.
"Despite the rapidly growing economy, many families in the Mekong Delta are still living in poverty," he said in an email interview. "Half of those households are living within temporary walls, and one tenth are under temporary roofs.
"Ironically, poor structures result in high maintenance costs. Many structures are damaged due to land subsidence and the harsh tropical weather. In addition, the area is at risk of flooding caused by climate change."
An example of so-called "vernacular" architecture -- a term use for buildings that respond to the local climate, materials and traditions of the region they're built in -- the S Houses' design can lower running costs for their inhabitants. Translucent panels allow natural light to enter, while a gap between the roof and walls creates natural ventilation, reducing the need for air conditioning.
With some homes in the series produced for as little as $1000, the use of local materials -- a hallmark of Nghia's work -- has helped to bring prices down further. Materials like bamboo and palm leaves are used in conjunction with steel frames, offering stability while respecting local aesthetic traditions.
"All the elements are assembled (using a) dry joint system," Inudoh added, "which enables construction by the residents without special techniques or machines. Consequently, the main structure of the latest prototype can be assembled in three hours."
In Asia -- just as in the West -- the luxury sector is now marketing prefabs as something more than a simple housing solution. Designers of high-end modular homes are also looking beyond the West for influence, according to Thai architect Sitt Therakomen.
"We are becoming more and more aware of how charming the local styles are," he said in an email interview.
Therakomen's firm, Agaligo Studio, has developed a floating house called X-Float, which is built off-site and towed to its destination by boat. Part of a riverside holiday resort in Kanchanaburi province, in western Thailand, the design draws on the architectural heritage of the region, where communities have traditionally lived in houseboats.
Materials once used to build the homes -- such as wood and bamboo -- were not viable for high-end hospitality, Therakomen said. But the design was, nonetheless, inspired by the bamboo rafts used by local river communities. Taking the rafts' rectangular structure as a starting point, the architect split and stretched the shape over two floors to form one-bedroom units with an outdoor staircase and roof.
"Our first priority was to look into not only local architecture, but also all the local landscape, lifestyle, culture and craftsmanship," Therakomen said. "This can further improve our relationship with local communities that have no real connection to imported Western-style prefabs."
Therakomen said that prefabrication cut his costs and construction waste, while reducing disturbances to resort guests. In nine months, his firm was able to build six of the units, which come equipped with plumbing and wastewater treatment.
"We went from from a primitive, man-made floating platform to a modern livable unit," he said. "People can sleep in it while feeling as if they're on a raft. This is how we interpret the vernacular."