Rob and Yuka’s DIY house is resistant to floods, even if the risk is low at 500 meters above sea level. © Cherise Fong
The house built by makers Rob Oudendijk and Yuka Hayashi weighs 4 tons. It has no foundation, its walls are made of extruded polystyrene foam and mortar, electricity is supplied by wind and solar energy. We visited this prototype DIY domicile, somewhere between Thoreau’s cabin and future abode.
Nabari, special report (words and photos)
A DIY floating house resistant to tsunamis and floods is the wild project of a Dutch-Japanese couple of makers, finally realized in the shadow of a forest in Japan. Engineer Rob Oudendijk is one of the main contributors to the Pointcast network of fixed Geiger counters. Designer Yuka Hayashi co-founded the company YR Design with him in 2008, dedicated to their ongoing project of the 100% DIY house.
A resident of Japan for the past 25 years, Rob Oudendijk dreamed of building a floating house. In 2011, after two years of researching locations and materials, the couple bought a plot of land in the shadow of the forest, near the city of Nabari, 50 km east of Nara, Japan. The site was chosen by Kitty-chan, their cat. Far from the coast, 500 meters above sea level, they would be able to develop their dream prototype in peace.
It wasn’t long before they set up a tent and began to build their prototype house out of XPS extruded polystyrene foam—a material that is light, strong, easy to handle and above all, 100% waterproof.
Construction proceeded empirically, as they erected the walls and adjusted the architecture along the way using 3D modeling software. The DIY builders had complete freedom, as the structure without a foundation is not only situated outside city limits, it is not considered a house by the municipality. Three years later, the “pink house” stands alone like an autonomous shack in the forest, while its inhabitants live almost self-reliantly, not unlike a 21st century Walden!
Upon arrival, the sound of streaming water creates a pastoral atmosphere. In front of the house is a windmill, solar panels and a rudimentary herb and vegetable garden. Behind the house are mushrooms, water pipes, compost boxes, gas tanks, a generator…
The house itself is hermetically sealed by silicon joints. The windows are made of acrylic, the XPS floor is elevated by 30 cm, the roof is reinforced, and the entire exterior of the house is covered with mortar to protect it against the sun and the elements. Only the large front door opens vertically like a spaceship, doubled by a screen door to keep out insects.
Inside, the kitchen is supplied with water purified by a silver ceramic filter, while electricity is stored in an arsenal of batteries lined up against the wall, continuously charged by solar, wind and hydraulic energy. Power automatically switches to the generator in winter (November through March). Only the shower water (above the bathtub still under construction) is heated by gas (supplied by the outdoor tanks).
The temperature of the room is regulated by a heat exchange system, whereby two separate air streams are filtered by a membrane in a corner under the roof—hot outgoing air from cooking or an electric radiator heats the incoming air. The next version of the system will pass through the floor, which already maintains a constant temperature of about 11°C. In a corner near the bed, a dehumidifier keeps humidity below 70%, while an evergreen snake plant (sansevieria trifasciata) helps improve air quality.
If the couple’s house is DIY, their lifestyle follows suit. Strictly vegan, they cook without oil on a single electric plate, have no refrigerator or freezer and store all their food in waterproof boxes under the counter. They drive into town about once every four days to do shopping and laundry, have no television but listen to streaming radio and music and work remotely via the LTE mobile network.
On the work table are the tools of a seasoned maker and tinkerer: soldering station, drawers full of circuit boards, mini Makerbot Replicator, CNC robotic arm… Rob is a member of Pointcast and a consultant for numerous other projects, when not experimenting with his own homemade inventions. Yuka, in addition to various design work, cultivates hydroponic sprouts.
The long horizontal windows, all without curtains, are designed to offer a view of the forest at all levels: the lower ones for Kitty-chan, the middle ones for a sitting position, and the top ones for a standing perspective. It goes without saying that the floating pink house is always flooded with daylight…
But isolated in the middle of the countryside, how to know before the next tsunami if this prototype house will really float? “I promise you it floats,” affirms Rob. “It’s a simple calculation. The floor alone has a capacity of 40 tons, while the house weighs only 4!”
More information on YR Design’s DIY house