Kawazoe Architects infuses serendipity inside River Sea residence in Japan

Serendipity and Japanese minimalism entwine within Kawazoe Architects' River Sea, a gracefully efficient house clad mostly in charcoal grey, custom made local tiles. Making more with less, the dwelling is located on Awaji Island in Japan's Hyogo Prefecture and revels in its meditative and uniquely meandering insides that complement its humble, well-designed exterior.

Conceived as an intimate, low slung private residence, River Sea fuses the vernacular and modern in its 427 sqm planning, composed of three functionally separate buildings (the entrance, guest, and the main volume) that are kept apart by pocket courtyards and united by a path that journeys across the layered domain. The one-story residential architecture was constructed and designed to suppress impact on its surroundings and sits at the mouth of a river that flows on its southern end.

The site is oriented on a north-south axis and was originally developed as a resort area near the sea. The private client, a CEO of one of the leading IT companies in Japan, chose the quaint location for their haven to take shape, away from the hectic city. The resulting design is modest and minimal, its optimal spaces driven by purpose and whose opaque exterior and top belie relaxing interiors are inlaid with sophistication.

"The placement of the three buildings is considered to ensure increased privacy for the inhabitant, as they move from the north to the south, along a straight axis,” says Juni-chiro Kawazoe, founder and lead architect of Kawazoe Architects. With a complete absence of openings, two flowy concrete leaves wind towards each other to form the access of the entrance building at the front. Successfully shutting off the senses from the outside, the dark sides of the entrance, the incomplete ceilings and the stone masonry floor create tunnel vision while entering the house from an open and bare patio, mimicking an earthy riverside cave-dwelling. On the way from here to the main building, one passes through two serene courtyards and guest areas that are decorated with pebbled paths, water basins, sparse greens and outdoor furniture.

"On the flow line of the path, the boundary between the inside and the outside becomes ambiguous, creating a space where both realms are united and at the same time, kept separate,” adds Kawazoe. The movement of the meandering path creates a broken, interesting line of vision that gives River Sea its continuous quality, its insides in constant flux, appearing like different scenes stitched in a film. The main "wall path" weaves through the residence, sometimes an exterior wall and then a wall of the living room that goes on to essay the background of a guest bedroom.

The three volumes are topped with flat roofs with timber undersides and extend horizontally, mounted lightly on the walls of the dwelling. The wavy entrance walls are dressed in Awaji border roof tiles, which are also employed as flooring in some parts. “There are subtle changes in colour and shape caused by uneven tile baking, and the power of the flame is expressed on the wall. We decided to keep it that way,” shares the Japanese architect.

Additionally, some of the walls are also finished with Awaji round roof tiles and Awaji plastering. According to the firm, this is what gives the concrete residential design its characteristic shadowy flavour. These border tiles are custom-made by arranging the materials and construction methods of "roof tiles" historically made in this area. The darkness of the tiles is provided warmth via curated lighting, panels of timber that line certain spaces and calming water features and plants placed outside. Connecting spaces between the three buildings become decks for simple outdoor lounging and barbecue evenings.  

The surrounding landforms and skies are captured in little pockets that can be seen from the inside, where the walls and the roofs fail to touch. True to Japanese minimalism, the interior design is inlaid with artful functionality articulated by bare walls, minimal décor and furniture in woody shades, and subtle lighting that line the spaces where the walls meet the floors and ceilings.

A ribbed timber screen separates the living area and dining room in the main building, with floor to ceiling windows that bring in the exterior courtyards. The washing area is kept at the back of the residence, with a square opening on the roof bringing in daylight. Most spaces of the residence look out onto the courtyards or always have access to the open skies.

Concrete walls clad in dark tiles, along with pockets of warm wood and courtyards, constitute a pared-down aesthetic that tiptoes between vernacular architecture and modern aesthetics. Utilising the site’s orientation in combination with a successfully well-crafted space, River Sea excels in its simplicity where the insides are in understated dialogue with the outside, an important ingredient in the house's minimal design language.

Project Details

Name: River Sea
Location: Sumoto City, Hyogo Prefecture, Kobe, Japan
Area: 427.07 sqm
Year of completion: 2021
Architect: Kawazoe Architects
Lead Architect: Juni-chiro Kawazoe