Houzz Tour: A Little House Makes the Most of a Triangular Plot
Clever architecture turns this surprisingly small Japanese house into a family home — with stunning river views
Houzz at a Glance
Who lives here: A couple and their two young daughters
Location: Tokyo, Japan
Structure: Wooden, two stories
Site area: About 561 square feet (52.1 square meters)
Building footprint: About 313 square feet (29.1 square meters)
Total floor area: About 594 square feet (55.2 square meters)
Architect: Kota Mizuishi of Mizuishi Architect Atelier
The house is the residence of a furniture designer, his wife, who works from home, and their two young children. They had previously rented an apartment in the area, but their dream was to build a house. One day they were drawn to Mizuishi’s office nearby. They didn’t have a large budget but wanted to build a house in the same neighbourhood. Mizuishi and the homeowners looked for a site and finally found this very small and narrow piece of land along the river.
Article 43 of the Japanese Building Standard Law stipulates that every property must be connected to a road at least 4 meters in width, either directly or by a driveway, in order to allow access for emergency vehicles. However, this was not the case here, as the lane next to the house is less than 4 meters wide. It was therefore necessary to contact the city and the surrounding neighbors, get a special permit and fit the design as much as possible to the regulation.
A buyer for such a piece of land is hard to find, so, luckily for the owners, it was offered at a considerably lower price than the market average for the area. The current homeowners asked Mizuishi if it would be feasible to build a home there at all. After considering how much living space they would be able to extract from the site, they concluded that it could be done, with some ingenuity. The project began to take shape.
With such a narrow structure, however, there is the danger that the house might fall sideways in the event of an earthquake. Then again, too many pillars would have diminished the interior space. Instead, the structure was reinforced internally with small, load-bearing walls, which also help divide the interior into zones (pictured in later photos).
Due to budgetary constraints, the architect chose a wooden structure.
The part of the first floor that appears to be indented allows for a parking space. “I was a bit surprised when I was asked to make space for a car on this tiny lot. It’s limited to a mini vehicle, but I was able to make room here,” Mizuishi says.
Additionally, despite the steepness of the roof, the house lacks rain gutters. It’s a radical solution that makes it appear as though the roof and walls are one. “It’s quite courageous not to have a gutter, but we have U-shaped grooves on the outer perimeter of the foundation, so we won’t have problems with rainwater drainage,” Mizuishi says.
Additionally, the entrance threshold is 4 inches (10 cm) in height and depth and consists of concrete clad in stainless steel. The homeowners wanted to make sure any flood prevention measures would be as unobtrusive as possible.
The entrance meets a mortar-finished concrete floor as well as the stairs, which lead up to the living room, dining room and kitchen. The large shoe cabinet featured on the right of the photo floats above the floor. This is to ensure that it doesn’t make this part of the house appear even smaller than it is. The spot under the staircase is taken up by a washing machine and storage. No space is wasted.
As there is a loft directly above it, the living room ceiling isn’t very high. However, thanks to the large windows on both sides, one never feels overshadowed.
Despite how small it is, the kitchen has a relaxed air thanks to the height of the sloped ceiling, which adheres to the shape of the roof. The ceiling’s dimensions are emphasised by the pendant light. The Nakajima Tatsuoki Lighting Design Laboratory designed the lighting, which consists of recessed lights throughout most of the house. These highlight the quality of the space without being overbearing.
Structural design: Ken.Nagasaka Engineering Network
Lighting design: Nakajima Tatsuoki Lighting Design Laboratory
Builder: Hirano Kensetsu