Prefabricated housing - Part 1

The Sun Daily

Posted on 8 October 2014 

GOING back about a decade, who would have imagined the speed and connectivity which internet messaging allows today. What about the microwave which permits cooking and re-heating in minutes, even seconds? In these fast-paced times where quick gets quicker in the blink of an eye, and a new word may need to be coined to describe the span of time faster than a nano-second. Houses which took years to build in an earlier era can now be erected in just a few months.

Prefab in general

Prefab is an abbreviation for prefabricated. It is a relevant term in the housing industry referring to prefabricated housing. The concept of "prefab homes" encompass several types of building techniques. Technically, it covers a house that has sections of the structure built in a factory and assembled on site. Industry professionals claim that "modular" and "panel built" houses come under the prefab label. The difference:

• Panel building – Accomplished by laying down the floor and then lowering each section of wall in to place, one at a time.

• Modular building – The house is constructed in separate box-like modules or sections which are then secured together to form a complete unit.

While modular building does not allow for additional structures like house extensions eg. garages, patios etc., by combining panel and modern-day modular building techniques, home designs can come in a host of options.

According to Daiwa House Group, a globally recognised conglomerate and industry-expert in prefab housing (and other businesses), the basic principle of prefabricated homes is a home that is fabricated in one location and then delivered to another.

Where it's commonplace

Talk prefab tech and Japan comes to mind immediately. A country where space is constrained, highly valued and costly (compared to land in Malaysia), its natives try best to conserve and make the most of what is available. Many live in small, compact, yet well-outfitted homes.According to a research done by Mathew Aitchison for the University of Queensland's school of architecture, "while the idea of factory-made housing failed in the West, the Japanese have made prefab housing work". The post-doctorate fellow visited the plants of four of the most successful industry manufacturers, Sekisui House, Sekisui Heim, Misawa Homes and Daiwa House. He reported that prefab homes in Japan are customisable and can be tailored to the customer's every need. Yet, he says that to the casual observer, prefab houses may look very much the same, irrespective of which company made them.

"Dimensions of rooms can be changed, the footprint of the building can be fitted to different sites within certain tolerances, and finishes and fixtures can be alternated … but the overall appearance remains the same: an interpretation of a generic western suburban house, clad in ceramic tiling, with a very predictable colour palette ranging from brown to beige."

Pros and cons

However, Daiwa House chief certified architect Kanta Tokuda says that there are many advantages in employing the prefab technique of building houses. "First and foremost is the time frame. Compared to traditionally built houses, prefab units only require a short construction period, less than half the usual time."

Benefits include:

1) Short construction period - While modules and panels are manufactured off site, the foundation is laid on site,
saving time.

2) Lesser manpower required on site – According to Tokuda, it only takes five men and three weeks to erect the main structure of a double storey house. It took four weeks and six workers to assemble the prototype house in Sunway Eastwood. Basically, only nuts and bolts need to be secured once the shell is in place, besides adjoining electrical wiring and plumbing.

3) High quality and standardised workmanship – Quality controlled uniformity due to factory-made conditions which produce products made to specifications. The outcome - lesser or very few defects that save cost, time, energy etc.

4) Responsible building – Environmentally friendly in terms of energy conservation as lesser manpower is required with a shorter and more efficient construction time frame. There is also lesser waste material on site. Materials used are also sustainable (steel and earth-friendly boards) and depending on how the home is put together, some can be dismantled and re-erected at another location.

Around the globe

Aitchison's paper reported that of the 495,737 detached, privately-owned new houses constructed in Japan in 2013, approximately 64,035 (12.9%) were prefab or modular. It also stated that Sekisui House produces 15,000 detached houses per year, and its manufacturing plant in Shizuoka produces 20 houses per day. His take on Japanese prefab housing: "the most advanced proponent of its kind in the world."

His view on the Australia market – "relatively small but reveals more diversity compared to the Japanese market. Companies like Happy Haus, Prebuilt and Tektum offer a wide range of housing products which are comparable in price to Japanese models". Still, in terms of highly efficient design and production process, he feels there is much one can learn from the Japanese.

In Malaysia, a memorandum of understanding (MoU) was signed between Japan's Daiwa Group and our Sunway Group. It allowed for a prefab prototype house to be built in the Sunway Eastwood development to facilitate a study on the feasibility, considering feedback from various parties including house buyers and investors and industry personnel. On a separate case, the government also signed an MoU with the Japanese on its PR1MA homes.

Design-wise, prefab houses need not don that homogeneous look, though factory manufactured and machine-driven via a programme, then catalogued.

For those who think prefab homes carry an impersonal, cold and emotionless design, log on to http://www.dwell.com/house-tours/slideshow/best-prefab-7-homes-we-love#1 and be mesmerised. Read our column next week for more insights on prefab housing.