Arai Family Residence (Chofu)

About the Arai Family Residence (Chofu)

The Arai Family Residence (新井家住宅, Arai-ke Jūtaku) is a farmstead in Irumacho, Chofu City, Tokyo, whose buildings date from the late Edo period to the mid-Meiji period, and whose five structures were entered on Japan's register of Registered Tangible Cultural Properties on April 25, 2014.

The five are the main house, the inner storehouse (uchigura), the outer storehouse (sotogura), the former silkworm rearing house, and the middle gate and wall. The main house and the inner storehouse are the oldest, both dated to the late Edo period (1830 to 1868). The outer storehouse, the silkworm rearing house and the gate followed in the mid-Meiji years (1883 to 1897), so the order in which the farm grew can still be read on the ground.

The Agency for Cultural Affairs describes the main house as a farmhouse that keeps the look of an old Musashino family seat inside its belt of trees, and the silkworm rearing house as a survivor from the days when silk farming was part of life on the edge of Tokyo. What makes the Arai Family Residence worth knowing is that the whole working farmstead is still together: the house, two storehouses, a farm building and a garden gate.

The owner is the Arai family, as recorded in Chofu City's list of designated and registered cultural properties (as of April 1, 2026). By that list, these five account for five of the eleven nationally registered properties in the city. Note that a different building, also registered as Arai Family Residence Main House, stands in Kitayamabushicho, Shinjuku Ward. It is an early Showa house with no stated link to this farmstead.

The Five Registered Structures

All five were registered in the same round, the 77th, under registration numbers 13-0338 to 13-0342. The Agency's database gives these dates and structures:

• Main house: late Edo period. Single-storey timber house, thatched roof under a temporary sheet-metal covering, building area 128 m²
• Inner storehouse: late Edo period. Two-storey earthen-walled storehouse, sheet-metal roof, building area 20 m²
• Outer storehouse: mid-Meiji period. Two-storey earthen-walled storehouse, sheet-metal roof, building area 35 m²
• Former silkworm rearing house: mid-Meiji period, altered in the mid-Showa period. Two-storey timber building, sheet-metal roof, building area 41 m²
• Middle gate and wall: mid-Meiji period. Timber gate with a sheet-metal roof, 1.5 m wide, and a timber wall with a sheet-metal roof, 8.5 m in total length

The alteration of the silkworm rearing house is dated 1946 to 1965. All five were registered under the same criterion, contribution to the historic landscape of the country. The point is less the design of any one building than the survival of a complete farm compound inside its woodland.

On November 15, 2014, the chair of Chofu's cultural property protection council, Inaba Kazuya, gave a public lecture on the city's newly registered buildings, with the Arai Family Residence as one of the two main subjects.

How the Arai Family Residence Is Laid Out

Piecing together the Agency's descriptions gives a rough plan of the Arai Family Residence. The main house stands in the middle of the plot and faces southeast. In front of it lies the front yard, and across that yard the outer storehouse faces north toward the house. The former silkworm rearing house stands right next to the outer storehouse on its east side, with its ridge running east to west.

Behind the formal rooms of the main house is the inner storehouse, joined to the house through a small room called the kuramae-zashiki, so it could be reached without stepping outside. From the front of the main house the middle gate and wall run west, dividing the front yard from the main garden.

In short, the main house, the outer storehouse and the silkworm rearing house frame the front yard, while the inner storehouse and the main garden sit on the quieter side. Each building has its own page with the details.

Visiting the Arai Family Residence

The Arai Family Residence is a private home owned by the Arai family, and Chofu City publishes no visiting arrangements for it (checked October 2026). The plot is wrapped in trees, and how much can be seen from the street could not be confirmed. For interior access, photography or any planned openings, the Chofu City Folk Museum (Kyodo Hakubutsukan, tel. 042-481-7656) is the office to ask.

The city has occasionally shown the buildings in other ways. In 2019 the Mushakoji Saneatsu Memorial Museum and the Folk Museum held a joint display on Chofu's old buildings that presented the Arai Family Residence in photographs and panels.

The farmstead lies in the residential area south of Sengawa and Tsutsujigaoka stations on the Keio Line. On the map it is roughly 1 km in a straight line from either station, so allow about 15 minutes on foot. Please stay off the private grounds and avoid photographing the family's home life if you look from outside.