In Tokyo, a spacious home with an 18m-long swimming pool in the basement

Moto Azabu is an upscale residential neighbourhood in Tokyo. Along its quaint pavements, there is a house that displays a reticent face to the street, with a two-storey blank, silvery-grey wall. There are no windows on this elevation to give clue to the domestic happenings, but within is an inviting sanctuary for the family who relocated to the city several years ago.

Designed by Japanese firm SAAD (Sudo Associates, Architecture and Design), the owner is part of the team that runs an international property development company Zekkei Properties. The business is particularly invested in Hokkaido, where they entered the scene early in 2005, creating many hotels and luxury properties including Elevation – Upper Hirafu’s first gated estate designed by renowned Japanese architect Kengo Kuma.

“The company also owns Fenix Furano and Fenix West – two hotels in Niseko that we designed. It is now focusing on developing residential works of a smaller scale in Tokyo,” shared SAAD’s founder Tomoyuki Sudo.

“Real estate prices in this area are among the highest in Tokyo, attracting demand from both within Japan and internationally,” Sudo commented. A small apartment building used to stand on the 278.1 sq m plot. The house, with a built-up area of 614.78 sq m, is considered generous in the city where most detached houses average a floor area of 98.3 sq m, according to the Statista Research Department.

The area is home to many houses such as these, aside from numerous foreign embassies and luxury apartments. “There are also many cafes opened by foreign brands, restaurants and art galleries, exuding an atmosphere of sophistication,” described Sudo. Other well-known buildings in the area include Tokyo Tower, Roppongi Hills and the newly completed Azabudai Hills.

When designing the house, Sudo had to address several constraints. These included the need for privacy from passers-by and buildings nearby – typical in Tokyo, where the walls of houses next door can be an arm’s length.

The footprint follows the shape of the plot, which stretches longer at the rear behind a neighbour’s house. Views were limited at the two sides, but the back of the house faced courtyards of buildings within proximity, so Sudo created large openings on the lower levels in this direction, aiming for “an urban architecture with a sense of openness”.

Sudo set back the house’s main entrance, creating a breather from the general urban density with a double volume space. The garage fronts the street as a buffer to the lift core and a guestroom, a wine room and utility functions located on the first storey. On the second floor are the master bedroom and children’s bedrooms, while the basement contains a guestroom, 18m-long pool and gym.

Gathering spaces are revealed on the third storey, where ample windows in the living-dining-kitchen area open the house up to expansive city views. On the rooftop terrace, this openness is magnified with all-round views and plenty of space for lounging and entertaining.

“Despite being in the dense urban centre, the terrace, laid with wooden decking, offers a private outdoor space. At night, the plants are illuminated, providing a relaxing atmosphere,” Sudo commented. A small kitchen here allows for barbecues should the need arises.

There is even a fireplace so that guests can enjoy the mesmerising view of twinkling city lights in cold weather. “Spending time by a fireplace, enjoying the spectacular views of Tokyo Tower and the surrounding skyscrapers, is undoubtedly a luxurious experience,” described Sudo. 

Compared to other parts of the house, the third storey also features higher ceilings that make the space feel commodious. “Roller screens and lighting boxes at the windows are both aesthetically pleasing and functional,” said Sudo. Two sides of the house on this level are set in from the perimeter, creating balconies where plants become a privacy shield and visual respite.

“Enveloped in plants, the spaces don’t feel urban,” Sudo remarked. A large tree in the neighbour’s courtyard forms a pretty composition outside the kitchen window, he added. At the rooftop terrace, plants include herbs for the family’s meals.

Throughout the house, strategically placed openings build connection between the interior and exterior. For example, the hallway where the elevator and staircase are located has large, glazed openings on the east and west direction.

“This allows natural light to brighten each floor and offer views of the city from the upper floors. At the basement’s elevator hall, the pool is visible through glass with natural light pouring in from the plants on the west side,” said Sudo.

In the basement, gardens along the perimeter, open to the sky, bringing in light and views. “To avoid the claustrophobic feel of underground spaces, the basement has been designed to mimic a secluded waterfront oasis, ensuring privacy while offering an open space surrounded by greenery and bathed in sunlight from above,” mentioned Sudo.

At the same time, ambient lighting also creates a cosy, cavernous atmosphere that augments the sensation of being underground. In the gym, a fully mirrored wall not only facilitates activities like yoga and weightlifting, it also “expands the perception of the space,” said the architect.

He shared that the children and their friends who visit use the pool sometimes, but the primary users are the owner and her husband. The owner was especially happy with the pool. “She used to swim 10km frequently in public pools when she lived in New York, and expressed delight that this activity is available to her in her private home in Tokyo,” said Sudo.

Sudo’s carefully planned layout means even areas deeper in the house enjoy some daylight and a sense of openness. For example, the master bedroom suite faces the street, so it is closed up with a blank wall. Sudo set in a corner of the block to create a small balcony for the adjacent walk-in wardrobe and master bathroom. When the two sliding doors between the bathroom and bedroom are opened, the latter enjoys the natural light that spills in from the balcony windows. Another window in the master bedroom is placed above the main door, facing the double-storey entrance foyer. A metal mesh, flushed to the front facade, affords privacy.

The strict form of the orthogonal house form is emphasised by minimal materials. But the ample plants poking out of the balconies bring some softness to the hard edges.

Sudo chose materials that are subtle and tactile, befitting a tranquil domestic environment that contrasts with the glossy, artificial materials cladding the luxury residences and hotels nearby.

For example, the exterior silver-grey silicate paint’s uneven finish offers a sense of depth. “The paint integrates with the concrete, enhancing the surfaces while preserving the natural texture. This accentuates a handcrafted sensibility. The silver layer captures and reflects the surrounding hues, resulting in a distinctive expression where a gradient emerges from the bottom to the top of the building.”

The interior is finished in dark textured tones so that the natural light at the windows is augmented – except the third storey, where white plaster and paint reflect the abundant natural light. Sudo added: “The kitchen is finished with ceramic tiles that matches the wall's colour and enhances durability.”

After living here since December 2023, the owner and her family are more than satisfied with their new home. Besides the swimming pool, the owners’ other favourite spots are the living room and rooftop terrace. “The rooftop view exceeded their expectations,” Sudo commented. “Given that this area is subjected to building height regulations, the stunning views will most definitely enhance the value of the building.”

The best compliment was when the owner proudly showed off her architect. Sudo shared: “We were honoured to be invited along with the owner’s close friends to her housewarming party, where she graciously introduced us as the architects of her house.”