This project is a renovation of a 43-year-old traditional Japanese house.
Located in Kasahara, Tajimi City, the birthplace of glazed mosaic tiles and still Japan’s top producer, the home belongs to a tile industry family. The client requested a complete overhaul of the floor plan to accommodate a new multi-generational household, where a grandmother and her grandchild’s family would live together. At the same time, they wanted the renovation to carry forward the memory of the house where the grandmother once lived with her husband and family.
The original structure followed a classic Japanese layout: two 8-tatami rooms side by side, opening onto a southeast-facing garden through a traditional engawa (a narrow veranda-like corridor). The living room was on the east side, with private rooms extending toward the northeast.
To better integrate daily life with the beauty of the garden, the two 8-tatami rooms were merged into a single, central living space. The engawa was transformed into a doma (a traditional semi-outdoor area) by lowering the floor level. This area now acts as a transitional zone that blurs the boundary between interior and garden. A set of lattice doors, reminiscent of traditional shoji, separate the doma and the living room. For the doors, instead of traditional washi paper, acrylic panels were used to preserve the visual connection to the garden while offering durability.
The doma guides affordance by lowering the floor level, becoming a lounge where one can view the garden from a different perspective than from the living room. When the grandmother’s friends visit, they can approach the living room without needing to step up the stairs, while enjoying a view of the garden while they chat. At times, it becomes a play area for young children, with family members watching over them. The relationship with the garden, which cannot be fully experienced from just the living room, is created by the 400mm difference in floor levels.
Kasahara is located in a basin surrounded by mountains, making it a region with harsh changes in climate. Summers are hot, and nights are chilly. In this house, the doma was conceived as a large 'air layer' that separates the exterior from the living room, following a passive design philosophy for environmental planning. Insulation was installed beneath the doma to prevent cold floors, and ceramic tiles with high thermal mass were used as the finish. In winter, the light from the low angle of the sun is absorbed and stored by the tiles, radiating heat to mitigate the temperature difference with the outside. During the summer, the high-angle sunlight is blocked by the eaves, and the inherent coolness of the tiles provides a refreshing atmosphere for daily life.
Today, an efficient combination of necessary functions is required for spaces such as the living room, dining area, individual rooms, and the corridors that connect them. A space like the doma, without a specific function, can be seen as a 'gap' in daily life. It can bring change to everyday life and enrich the experience of living.