In the renovation project of a house in Kodaira, Tokyo, mtka architecture studio has added a mezzanine as a large elliptical void. The two-storey building, built twenty years ago, has a top floor space of 88 square meters, enhanced by a large south-facing window and a sloping roof, where the kitchen, dining room and living room are located. 

The new structure, that was built right under the roof and accessible by a staircase, redefines the interior space creating an added environment running around the whole perimeter of the room, narrowing along the longest sides. With its white surface in contrast to the wood of the ceiling and walls, this new mezzanine floor is fixed at 1.80 meters above the floor.

Moreover, the design provides a better control of sunlight and natural ventilation thanks to the air coming on through the window after the elimination of the existing bracing.