Daylight funnels into this dark concrete house in Japan through two narrow light wells in the roof.
Designed by Japanese studio Tomoaki Uno Architects, the two-storey house in Nagoya contains just three rooms; a living room and bathroom on the ground floor and one bedroom on the half-sized first floor.
Aside from the skylights, the building has no windows in the double-height living room, creating a space that is dimly-lit.
Despite this, architect Tomoaki Uno told Dezeen he "values sunlight" most of all. "The inside is dark in these photographs, but that expression varies from one day to another," he said.
The interior walls are left as stark concrete.
This theme continues on the exterior, where the only relief from the bare concrete walls is a metal door that reveals an entrance on the side of the building.
Uno described the project as a once-in-a-lifetime opportunity. "I do not make such an architecture all the time," he said.
Other houses in Japan we've published this week include a residence with sheds on the roof and a house with courtyards punching through its walls.
See more Japanese houses on Dezeen »
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Here's a few extra project details from the architect:
House at Ryusenji
Location: Nagoya, Aichi
Prinicpal use: residence
Site area: 118.33 sq m
Total floor area: 69.94 sq m
Structure: wall reinforced concrete
Scale: 2 storeys
Above: plans and section - click above for larger image