A series of triangular and rectangular platforms create numerous floor levels inside this house in Osaka, Japan.
Designed by Tato Architects, House in Takatsuki is a three-storey building containing 16 different floor levels.

The floors gently rise in a spiral, making it easy for people to move up and down the building.
There are no staircases ? instead residents walk over wooden blocks, shelves and other pieces of furniture to move between the different levels.

"Rather than using walls and different floor levels to clearly divide the space into various functions, everything loosely connects and disconnects from each other through stepped floors," explained Tato Architects founder Yo Shimada.
"The idea is to create a sense of expansion inside a small house, so that you would find yourself on top of a rooftop in one moment, and tucked beneath a floor in another."
Shimada describes the interior as a functional cave, although the layout actually has a very strict geometry.
In plan the building is a rectangle, nine metres wide and 5.5 metres deep, but with two of its corners missing. Internally, partition walls all run at 45-degree angles to the exterior walls. This divides the layout into a series of triangles and rectangles.

Various furniture elements negotiate the changes in level. For instance, a dining table in the kitchen lines up with the floor of the next level up. Elsewhere, a desk does the same thing.

There is also storage slotted in under t...