The site is a plot of approximately 1,350 m² located in Toyokawa City, Aichi Prefecture, situated between the Tōkaidō and the Old Tōkaidō roads. It lies within the area of "Akasaka-juku," which was the 36th post station on the Tōkaidō route; all the traditional inns (*hatago*) that once operated there have since closed. While the area was once bustling—even depicted by Utagawa Hiroshige—its decline is attributed to being bypassed by the JR railway line. Behind the site rise mountains in the 300-meter range, including Mt. Miyaji (361 m).
In urban areas, new construction often involves the repetitive cycle of demolishing existing buildings to erect new ones, leading to rapidly changing streetscapes. In contrast, areas like this one—where the landscape remains relatively stable—often offer greater latitude regarding both space and time, allowing for the construction of new buildings while preserving older, disused structures. This "breathing room"—where the unneeded (old) and the needed (new) coexist—might well be a characteristic unique to regional environments.
Occupied continuously since the Edo period, this site has evolved over six decades to accommodate changing lifestyles. Through successive rounds of new construction, additions, and partial demolitions, the property has housed a main residence, gardens, fields, storehouses (for crops, household goods, and farm tools), waterways, and a rental parking lot. When this project began in 2011, the family was living in the main house, while a dilapidated two-story structure stood next door. With their children now grown and living independently, the couple decided to retain the main house—now too large for just the two of them—for use as a vacation home or guest quarters, and to build a new, smaller residence on the footprint of the dilapidated house. We sought to incorporate the "breathing room" inherent in this environment into the architecture itself.
We designed a compact, single-story structure (approximately 8.2 by 7.3 meters) topped by a hipped roof with deep eaves, creating "margin" spaces—areas sheltered by the eaves—on all four sides. These sheltered areas serve as resting spots for the couple as they tend their fields. Additionally, the space above the interior core was left open, without a ceiling, to further create a sense of surplus, unprogrammed space. It serves as both storage and usable space. A lifestyle that allows for ample space on the property means there is no need to immediately dismantle unneeded elements; instead, the home evolves gradually while retaining areas of surplus space. In this context of ongoing transformation, the current project represents a form of "renovation" of the site's environment itself. The accumulation of structures from different eras surely contributes to a "rich life" for the residents.
