A doorway is the only opening in the concrete facade of a home in Tokyo designed by local studio MDS.
Architects Kiyotoshi Mori and Natsuko Kawamura wanted Shirokane House to make the most of its small site, so they designed a three-storey structure which angles outwards and upwards to create extra space and bring in more light.
"There are basic requirements for a house, where people live, such as privacy protection and ample daylight and ventilation," they said.
"It, however, takes a little ingenuity to satisfy such requirements under a given condition that a site is surrounded by the neighbouring buildings."
The door is on the middle floor and leads to a high kitchen and dining room that receives natural light through a pair of high level windows.
A steel and timber staircase leads up to the top floor which includes the living room.