These Geothermal Homes Use Heat From the Mountainside They're Built Into

By Bryan Lufkin on at

Japan is a country that’s 75 per cent mountains, which makes construction more than a little tricky. One architect’s solution? Build homes into the mountains, then rent them out. Tenants then score natural geothermal insulation in an abode that’s downright Seussian.

This cosy, seven-unit residential complex is nestled at (and into) the foot of Mineyama Mountain in Takamatsu, Kagawa prefecture, in southern Japan. The great thing about sticking buildings directly into mountains is that internal temps are controlled geothermally, since the building is almost completely surrounded by earth. While this yields a base temperature of around 15°C (60°F), heating and cooling tubes are buried below. They feed fresh air from an air tower atop the slope and to the individual units, cooling and heating to optimal temperatures.

Real Estate Japan describes an additional “insulating layer of air between the inner wall, as well as the ceiling and floors, which prevents heat movement by convection, similar to the way a thermos bottle works”.

These Geothermal Homes Use Heat From the Mountainside They're Built Into

The Shire-like complex, designed by architect Keita Nagata, is called Miyawaki Gurindo. It took two-and-a-half years to finish, and totals five floors. Each unit’s roof serves as the garden for the unit the next floor up. Nagata cut construction costs by building into the slope and adapting to its natural shape, rather than levelling the site and tacking on a retaining wall.

You’re probably thinking, 'what about earthquakes?'. Well, Miyawaki Gurido’s made of steel-reinforced concrete. Real Estate Japan writes that it’s “generally considered the safest material for minimising earthquake damage.” Unit sizes range from around 320 square feet to around 800. Rent for the smaller units is 66,000 yen (around £340) and the bigger ones are going for 135,000 yen (a bit under £700).

Check out more buildings that get up close and personal with the good Earth here. [Greendo via Real Estate Japan]

These Geothermal Homes Use Heat From the Mountainside They're Built Into

Image via Global Center

These Geothermal Homes Use Heat From the Mountainside They're Built Into

Images via Greendo and used with architect’s permission