Resolving architectural challenges through effectively simple yet strategically profound interventions is both relevant and often elusive to achieve. It is a multifaceted pursuit that demands analysis, intelligence and a balance between creative innovation and restraint. For instance, how does one ensure adequate natural light and ventilation in a structure without perforations on its facades, while also harmonising functionality and aesthetics in cohesion?

When presented with a similar predicament for their recent project, Studio Cochi Architects dissolved site constraints while balancing client requests through geometric purity, stark compositions in concrete and tactical architectural restraint. The House In Nishizaki, a single-family contemporary home rises prominently in a newly developed residential area in the south part of Okinawa’s main island in Japan, reclaimed by a landfill. At first glance, this cubic dwelling appears to hover just above ground level, its exterior a textured grey concrete slate, impenetrable, closed off.

This is delightfully contrasted by a light-filled, ultra-minimal residential interior achieved through advantageously placed geometric skylights, framed glass apertures and courtyards. These respond to the dual needs for openness and privacy while maximising light and airflow for the inhabitants—a couple and their child.

A mix of architectural typologies defines the site’s surroundings, encompassing commercial facilities, industrial parks, residences, schools, sports parks, fishing ports, and other structures of various uses and scales. To the site’s north lies a designated residential zone, and to the south, a bustling commercial area stretches across a large highway. According to the architects based in Okinawa, this results in the north side being relatively quiet, while the south gets noisy at times due to heavy traffic. To the east and west, neighbouring houses remain densely packed, reflecting a trend of increasing vacant homes amid developed areas.

“While Okinawa has a unique and majestic natural environment, urban areas have this chaotic landscape. In addition, typhoons occur throughout the year, and one must be prepared for disasters. In such an environment, the challenge was to maintain distance from the city and to ensure a comfortable indoor environment,” explains Toshiyuki Igarashi (lead architect) and Hiroyuki Inaoka (assistant architect) at Studio Cochi Architects.

In line with the site’s demographics, the client requested a residential design that would chamfer or completely screen their line of sight from these surroundings, while letting in as much natural light and wind as possible, to have “their own urban oasis,” the Japanese architects relay. To achieve this, they decided on a contemporary, cubic grey volume following a rectangular plan aligned with the site’s shape.

The 91.50 sqm residential architecture houses public rooms on the first floor connected to the town, and private bedrooms and bathrooms on the second. Since the façade design is sans perforations, the courtyard and skylight are integrated into the north-south direction, where light and wind can be easily channelled into the dwelling. Due to their placements, spatial compositions and pleasant pockets mushroom inside, complementing and conversing with other elements of the private residence.

Facing the residential area, the courtyard on the home’s north serves as an imperceptible ‘buffer zone.’ It maintains a faint transition that connects to the town without getting too closed off, designed as a continuous space that extends from its approach to the tatami room (which is also a parlour). This feature also carefully takes into consideration the line of sight to the interior design.

Meanwhile, the courtyard design on the south side of the contemporary architecture functions as a thick, solid buffer zone between the town and the staircase room, “enhancing the livability of the courtyard and the living room,” according to Studio Cochi Architects. They also intended for the staircase design to be used as a ‘dimly lit’ room, so it was conceived as a larger space to accommodate chairs and other items.

“By creating a strong and weak buffer zone with the city and allowing space for natural light and airflow, we believe we have created a three-dimensional house that can accommodate the various activities of daily life in relative peace while living in a densely populated residential area,” Studio Cochi Architects relays.

The pared-back House in Nishizaki is conveyed with aplomb vis a vis concrete as the protagonist, the material's opacity manifesting as the barrier between the town and the home like the residents wished for. While the abode's roof is made of metal trowel-finished concrete coated with a heat-shielding waterproof layer, the exterior walls are finished in fair-faced concrete with a clear coating. Concurrently, the flooring inside the Japanese architecture is made of polished concrete with a clear coating as well as tatami, and the walls and ceilings are finished in polished fair-faced concrete.

A monastic aura perfumes the insides of the concrete architecture, taking on a serenely imposing persona sans curated art on walls, saturated colour additions, accompanying sculptures, or any vibrant signs of home décor. Apart from subtle shifts in the texture of concrete, the only accents of relief are relayed through wooden furniture and light steel fittings, which were made in Inaoka’s workshop. “I would like to expand the possibilities of craftsmanship that are not dependent on the mainland but are provided within the prefecture,” he says, sharing a commitment to regional craftsmanship and sustainability through local materials and skills.

“When we think about architecture, we place great importance on the traditions and environment of the region,” Igarashi and Inaoka tell STIR. “Many traditional homes are rooted in their local environment and have a rich relationship with nature [and] context. There is a wisdom and ingenuity that has been built up over time, which we interpret in a modern way and reconstruct as architecture,” they add.

The home’s cubic concrete hunk begets refreshingly light and airy interiors, its perceptions gallingly honest, despite the primary material’s heft and continued greyness, something that Studio Cochi Architects deftly display in another one of their projects, the House in Sonda. Straddling pockets of spatial intrigue, serenity and quintessential Japanese minimalism, the House In Nishizaki conveys restrained beauty and discipline through calculated and gestural geometric compositions, precise lines and angles and the interplay of light with solid surfaces, some sentient, others patiently angled or curving.

What's interesting is how, at the owners' request, the architects achieved a coveted balance of privacy from the outside and openness from the inside, ensuring the occupants never feel exposed in their own home. This project conveys and embodies a richness in restraint. Most thoughtful outcomes often hinge less on architectural ego and more on genuinely attending to what's necessary.

Project Details

Name: House In Nishizaki
Location: Nishizaki city, Okinawa, Japan
Gross Built Area: 91.50 sqm
Year of completion: 2023
Architect: Studio Cochi Architects
Design team: Toshiyuki Igarashi, Hiroyuki Inaoka; Masayuki Takata (RGB Structure)
Builder: Nansei Corporation