A small company in Japan has come up with a surprising use for polystyrene foam, a packing material that most people throw away after buying a new product. The material is being used in the construction of homes, replacing more traditional materials like concrete or wood.
A builder claims a home in a dome is the shape of things to come in building construction. Not the shape so much. What is unusual here is the material.
"We developed this material ourselves," the builder said. "The structural frame is made out of polystyrene foam."
The company behind this technology has just 30 employees. It's based in Kaga City, central Japan. The material can be molded into almost any shape. But that's just one feature that appeals to the company president.
"It doesn't rot like wood, or rust and turn ragged like steel," said Katsuyuki Kitagawa, president of Japan Dome House. "My desire to use this material became stronger by the day."
But there was a problem. Regular polystyrene foam is no match for concrete or steel when it comes to holding up a roof. If the company wanted official permission to use this material, it had to work out a way to make it stronger.
Polystyrene foam contains lots of air: the larger the bubbles, the weaker the material. So Kitagawa's team focused on increasing density. Basically, making the bubbles smaller. The result was a much stronger substance.
The tough, durable material can support weights of up to 10 tons. The foam is molded into panels, ready for assembly. Interlocking grooves make this a simple process. Workers can put up a foam house in a matter of hours. And it's cheaper than comparable structures made from wood.
The new technology has received the government's seal of approval as a building material -- a world first. Dome structures are already in use. One such structure functions as a mountain lodge.
"This type of room is quite unusual," said Masaya Konishi, owner of the Aso National Park Healthful Forest. "The families staying here have enjoyed using it."
Polystyrene foam is also showing up in the walls of homes and restaurants. As many as 1,000 buildings have been constructed with this material across Japan.
Greenhouses are another potential application that makes use of the material's air-tight properties. The dome house company has built an experimental greenhouse to test the idea.
"Currently, greenhouses are at risk of collapsing from heavy rain or typhoons," said Daisuke Harada, a manager at Aso National Park Healthful Forest. "Since polystyrene foam domes are stronger, we have a lot of confidence this could be a promising market for us."
The foam is also an insulator. That makes it easier to maintain constant temperature and humidity, allowing stable cultivation all year round. Inquiries are coming in from greenhouse owners overseas. And local governments in Japan are looking into constructing foam shelters. The dome manufacturer is confident it's opened the door to a market that's destined to grow.