Arched, rectangular and pentagonal doorways cut through the three bowed walls that frame the dining room of this apartment by MAMM Design on the outskirts of Tokyo (+ slideshow).

The Tokyo-based studio reorganised the interior of the 30-year-old apartment, in the Sagamiono area of the Sagamihara suburb, for a mother and her two daughters. The project is thus named Apartment Sagamiono.

Stripping away the regimented original floor plan to create more fluid spaces, the designers added three gently curving walls to create a new family dining room in the heart of the home.

A lounge, computer room and three bedrooms are tucked behind the walls around the periphery of this central space – most of which are in the same locations as before the renovation.

Doorways with arched, pointed and flat tops frame views out of the dining area, through both the lounge and one of the bedrooms, towards a long balcony that runs along the south side of the apartment.

"[The apartment's] wide frontage towards the south was very attractive, but the existing plan was a stereotypical one," explained architects Akira and Maya Mada, the two founders of MAMM Design.

"The first step was to remove most of the existing partitions, except the bathroom, to create one big space."

Two of the curving walls meet at a point to create the pointed opening in front of the glazed balcony doors, while arched and rectangular doorways are positioned on either side.

The third wall peels away from others, leaving a wooden breakfast bar on one side of the kitchen open to the central living space.

"The existing kitchen was closed and separated from other parts," added the architects. "It was not an ideal situation for the client, who wants to enjoy the scenery of the wide frontage and to communicate with her daughters."

The new walls stop 20 centimetres short of the ceiling, providing privacy for the bedrooms but also allowing light and noises from the peripheral rooms to filter through to the heart of the apartment.

While the central area has pale grey floors, vibrant green-yellow flooring in the adjacent rooms accentuates the curving walls.

Akira and Maya Mada founded their studio in 2012. Other projects by the pair include the remodelling of an attic apartment in Amsterdam, where a kitchen was sunken down to makes room for a mezzanine above.

Photography is by Takumi Ota.