Nori Architects' 'Toyota Gem': A Stunning Minimalistic Dwelling Redefining Space Efficiency

Toyota City, Aichi Prefecture - Nori Architects, renowned for their forward-thinking designs, have introduced a groundbreaking urban housing prototype designed to meet the needs of a young couple and their two children. Situated on a narrow site flanked by bustling streets and neighbouring buildings, this innovative dwelling redefines space efficiency and offers a refreshing approach to sustainable living.

With a compact box-like structure measuring 2 ken (3.6m) in frontage by 7.5 ken (13.6m) in depth, the residence spans two floors, totalling 30 tsubo (100m2) in the area and standing approximately 6m tall. The architects have ingeniously divided the space into three levels, optimizing functionality while maintaining an aesthetic appeal.

The heart of the home lies in the expansive living room, adorned with a large window on the southeast wall that seamlessly connects the inhabitants with the urban void beyond. On the street-facing side, a covered terrace embellishes the dining room and kitchen area, featuring a mesh front and translucent walls. This design choice allows an uninterrupted flow of natural light and refreshing breezes while preserving a sense of privacy and distance from the city.

In their quest for year-round comfort and energy efficiency, Nori Architects prioritized the development of the exterior skin and mechanical equipment. Despite working within a limited budget, the team ingeniously combined reduced materials and affordable equipment to achieve outstanding performance. By exposing the wood structure, base, piping, and wiring, the architects created a warm and inviting atmosphere, enabling residents to comprehend the building's structure and carry out their own repairs and modifications.

Notably, this project represents a forward-thinking response to the global environmental crisis. Nori Architects aimed to minimize construction waste and reduce the overall use of materials. The result is a delightful dwelling that seamlessly integrates the indoors (family) with the outdoors (city), providing abundant natural light, invigorating airflow, and utilizing sustainable materials.

The architects' ingenuity extended beyond aesthetics and sustainability, as they also prioritized safety and cost-effectiveness. To achieve high earthquake resistance (Grade 3), load-bearing walls constructed with structural plywood and steel braces were strategically placed at both ends of each floor in a shorter direction. This design choice not only enhances stability but also ensures spatial flexibility and transparency.

Further optimizing the construction process, Nori Architects simplified the roof framing by utilizing 3.5" square timbers atop exterior insulation, creating a folded roof over baseboards and asphalt roofing. This clever strategy eliminated the need for rafters and reduced the number of components required, streamlining the building process.

With a strong focus on energy efficiency, the dwelling boasts high-performance window sashes, eaves, and exterior insulation. These features contribute to a commendable UA value of 0.49 (ZEH+ standard) and an ηAC value of 2.2 (exceeding the energy conservation standard). The architects also implemented a cost-effective ventilation system, utilizing fans and ducts to distribute warm or cold air from a single under-floor air conditioner to each zone, ensuring a comfortable thermal environment throughout the year.

Architects: Nori Architects

Area: 88 m²

Year: 2022

Photographs: Jumpei Suzuki

Lead Architect: Norihisa Kawashima, Nori Architects

Lighting Advisor: CHIPS LLC.

Constructor: TOKORO

Design Team: Norihisa Kawashima, Takuro Kunitomo

Structure Engineer: Seiji Okawa

Textile Designer: Yuki Tsutsumi

Equipment Advisor: Kozo Takase

Country: Japan