Project Name: Addition and Subtraction House

Location: Chiba, Japan

Design Team: S Design Farm

Building Area: 84.46 m²

Completion Date: October 2023

Photographer: Yasuyuki Kojima

Feature：

Project - Japanese architects Kuki Health and Masako Kuki of S Design Firm have redefined residential design with their innovative " Addition and Subtraction House," a compact 65-square-meter (interior) home in Chiba that challenges conventional notions of architectural richness during the post-pandemic era.

Driven by a profound philosophical inquiry into the essence of prosperity, the architects have crafted a dwelling that masterfully balances "enrichment through addition" and "enrichment through subtraction." The project emerges as a sophisticated response to rising construction costs and evolving domestic expectations, demonstrating how architectural innovation can transcend spatial limitations.

The home's most striking feature is its unconventional "outdoor living" space—essentially a hollowed-out area that remains partially connected to the interior. This ingenious design creates a semi-controlled exterior zone that embraces unpredictability, allowing spontaneous interactions with nature, from unexpected wildlife visitors to casual moments like impromptu fire pit gatherings.

Technically exceptional, the house achieves high-performance sustainability through meticulous design strategies. Featuring top-tier thermal insulation (Grade 6), triple-glazed windows, and a 6kW solar power system, the residence achieves near-zero energy consumption while maintaining exceptional indoor comfort. The architects report maintaining stable indoor temperatures between 20-25°C year-round with minimal energy expenditure.

By deliberately constraining the interior to 65 square meters and incorporating a 33-square-meter loft, the design exemplifies a nuanced approach to spatial efficiency. The architects prioritized creating emotional richness over pure square footage, proving that architectural quality transcends physical dimensions.

This residential prototype represents more than just a home—it's a manifesto on contemporary living, challenging architects and inhabitants to reimagine prosperity through thoughtful, sustainable design.

Design Team - Founded in 2008, S Design Farm Co., Ltd., led by Takeshi Shikauchi, embodies a profound dedication to crafting spaces that merge sustainability, comfort, and architectural ingenuity. As a first-class architect's office based in Tokyo, the firm is renowned for designing high-performance, energy-efficient homes and dynamic interiors that inspire everyday life. The design philosophy emphasizes balance—prioritizing thermal insulation and airtightness without compromising the harmony between architecture and its natural surroundings.

Under Shikauchi’s leadership, who is also a seasoned lecturer at prestigious institutions such as Tokyo Metropolitan University, S Design Farm has garnered numerous accolades. Recent achievements include the Asia Design Prize Gold Award 2023 and nominations for the ArchDaily Building of the Year 2023 for their innovative "Addition and Subtraction House." Their "Waterfall Villa" has also received international recognition for its luxurious yet sustainable design ethos.

Specializing in custom residential projects and full-scale renovations, S Design Farm incorporates cutting-edge techniques to achieve ZEH standards and nearly no-heating homes. Their commitment extends beyond technical performance, fostering spaces that embrace subtle natural changes and enrich the lives of occupants. With each project, the firm exemplifies a dedication to excellence, shaping architecture that is as functional as it is inspiring.