How domed houses are made from polystyrene foam in Japan (17 photos)

The classical understanding of materials for the construction of residential buildings is gradually being eroded and modified. Until recently, windows made from PVC profiles caused serious concern and mistrust; today, fundamentally new construction solutions have already appeared for the construction of an ordinary one-story residential building. These are Japanese houses made of polystyrene foam.

More precisely, from extruded polystyrene foam with a density of 30 kg/m3, which is well known in the construction industry as one of the most effective materials for thermal insulation of walls.

Relatively recently, just five years ago, the Japanese construction company Japan Dome House proposed and began producing a private one-story house of a fundamentally new design and design. The building was a dome or hemisphere with walls made of polystyrene foam reinforced by mechanical processing. In addition to numerous technical and technological advantages, the new Japanese house looked like a real building from the future, quite stylish and spacious.

A house made of polystyrene foam is distinguished by an absolutely innovative approach to organizing housing construction: the building was not built in the old classical sense of the word, its walls were assembled from component parts, ready-made door and window blocks, which means that construction costs were record low.

The frame and walls of the house were made of the same material - polystyrene foam, and were assembled, literally, like a children's construction set, from industrially stamped ready-made sectors;

Due to their shape and light weight of the walls, dome houses did not require a frame or a rigid foundation; the building could be installed on a prepared round platform made of sip panels or OSB boards.

As a result, the Japanese house made of polystyrene foam turned out to be spacious, warm and very cheap, even by Russian standards. The cost of one set of domed house with a base diameter of 8 m, a ceiling height of 4 m and a wall thickness of 10 cm was announced at $3,500.

The first thing that catches your eye when familiarizing yourself with the design of the house is the relatively small thickness of the walls of the building. The manufacturing technology provides for a wall thickness with laid outer and inner covering from 100 to 190 mm. The manufacturer believes that given the shape of the house, this wall thickness is enough to withstand a wind force of 25 m/s and any thickness of snow cover.

The technology for building such a house from polystyrene foam has been worked out by Japanese developers almost to the smallest detail.

Walls or segments of a house are produced in industrial furnaces and presses in the form of finished units. The site for the building is leveled in advance and fixed to the ground using a light pile foundation.

If the terrain is complex, has slopes and fluid soil, Japanese experts recommend making a circular shallow foundation. But in the classic version, a Japanese domed house can generally be located on rocky rocks in the mountains or in wetlands, without any modification of the walls and shape of the building.

After the foundation is prepared, walls and a central fixing ring are installed under the house, acting as a strength element. Next, windows and doors are installed in the window and door openings of the walls, the floor covering is laid, the walls are painted, and electricity and communications are supplied and connected in the finished channels inside the walls.

The outer surface of polystyrene foam walls must be plastered and painted. Japanese builders recommend using a polyurethane foam resin coating, which effectively protects the foam of the house walls from erosion and the sun.

A one-story house with a base diameter of 7-8 meters, depending on the configuration and layout of internal partitions and walls, can have a total area of 54-60 m2. By the standards of Japanese architects, this is quite enough for a comfortable stay for 3-5 people.

If necessary, you can build a boathouse version of a Japanese house from polystyrene foam, whose shape is not round and elongated; this will further increase the usable area of the building without increasing the load on the walls. Such options are supposed to be used for warehouses and office premises.

If desired, you can arrange a second floor inside the domed house, install ceilings and decorative walls, which will give a level of comfort comparable to typical Japanese city apartments. The modular principle allows you to assemble from several modules a house with a large area of ​​room and even an entire town with transitions and several levels of movement.

The main advantage is the high level of thermal insulation of the material. A house wall made of foam plastic 100 mm thick has the same thermal conductivity as a 1900 mm wall made of sand-lime brick, 350 mm wood or a 4800 mm concrete wall.

The strength of extruded foam reaches 45 kg/m3, which is very little for a building load-bearing structure, but with a wall thickness of 200 mm, its strength will correspond to a wooden house with a wall thickness of 40 mm.

After applying a protective coating to the foam, the durability of a Japanese house will be up to 60 years of guaranteed operation.

Low water absorption allows you not to be afraid of even the dampest soils, intense rains and heavy snowfalls.

But not everything is so rosy in the construction of Japanese polystyrene foam houses. First of all, polystyrene foam is very resistant to high temperatures and burns well, releasing large amounts of gases.

In addition, under the influence of solar radiation, the foam plastic of a Japanese house intensively crumbles and collapses. Therefore, for protection, it is recommended to apply a thick, up to 5-10 mm, layer of decorative plaster or other protective coating that absorbs ultraviolet radiation. Metallized coating based on aluminum is recognized as the most effective.

The Japanese technology for building a domed house was quickly picked up in Europe, with a slight improvement in the material for its construction. Today, it is often proposed to build a Japanese dome house not from pure extruded foam plastic, but from polystyrene concrete. The Japanese domed house has become much heavier and more massive; now its construction requires, at a minimum, a shallow foundation and drainage devices.

The house has retained its excellent thermal insulation and strength, but the high specific gravity of polystyrene concrete, reaching 200 kg/m3, has changed the house assembly technology. In the classic version, the 1/8 segment of the dome of a Japanese house was freely lifted and installed by only two people. Now, to perform such work, you need a crane and a special vehicle for transporting large blocks. It cannot be said that the design of a Japanese house in a new technological solution has lost its attractiveness, but it has become significantly more expensive.

Positive changes include an increase in the strength of the walls and the possibility of forming domes with a high ceiling height, up to 5-6 m. In addition, the polystyrene concrete version of the Japanese house is more suitable as permanent buildings for garages, warehouses, hangars, and parking lots due to the greater strength of the walls , which means greater resistance to burglary and intruders entering the building.

The layout and internal structure of the house, conceived and proposed by Japanese specialists, is very well suited for the construction of small cottages in the highlands for ski and mountaineering towns. The good thermal insulation of polystyrene foam and the wind-resistant shape of a Japanese house fit like no other.

Such houses can be used to create temporary housing for any purpose, and the level of comfort will ensure long-term living in domed Japanese towns.