This Japanese Home Has a Sunken Interior That Blends Into the Earth

The Pit House in Japan has smooth, rounded walls and a subterranean kitchen and living area.

This unusual 1,256-square-foot residence in Okayama Prefecture, Japan, looks like a simple wooden box from the outside. However, the interior features a surprising layout with a sunken living area set within a dug-out "pit" in the ground. 

Designed by Hiroshima–based UID Architects for a couple with a young child, this residence—aptly named the Pit House—has a foundation that’s 3.3 feet higher than the road, with circular dug-out sections in the middle.

The house is suspended above a landscaped garden.

The box-like wooden structure contains pit-like spaces that dip below the raised foundation level.

The home's organic form embraces the outdoor environment much like a large garden pavilion. The sunken living area follows the contours of the terraced land, opening up views to the north. 

The upper volume is supported by slender, branch-like metal posts.

The house is located on a terraced hill in Okayama Prefecture near the Seto Inland Sea in Japan.

A glass ceiling shelters steps leading to the entrance.

Using predominantly concrete and steel, the architects built the program over six levels. The common areas are located on the ground floor, which has a sunken concrete cylinder. Above this circular "pit" lies a floating box structure supported by branch-like steel columns.

A doorless sleeping space is located within the mezzanine level.

A bedroom is located within the column in the middle of the house.

The circular kitchen and dining area feels like part of the garden.

According to UID Architects’ founder Keisuke Maeda, the Pit House is designed to meld with the surrounding landscape. "It’s as if the site’s natural environment, and the architecture coexist harmoniously. The house has become a part of the landscape," he says.

Indoor plants and rocks create a strong visual connection to the outdoors.

The home's unique shape creates bright and open communal zones as well as cozy, private nooks. Plywood, exposed concrete, and cherry wood floors give the interiors a warm, almost treehouse-like atmosphere. 

The living area features built-in concrete bench seating.

The simple, clean-lined kitchen and dining area is the heart of the home.

Project Credits: 

Architect of Record: UID Architects 

Builder: Nakamura Construction Co.Ltd 

Structural Engineer: Konishi Structural Engineers 

Landscape Architect: Toshiya Ogino Environment Design Office  


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