Hisa Kinzoku Kogyo Former First Factory

Hisa Kinzoku Kogyo Former First Factory: Daylight from a Raised Ridge

The Hisa Kinzoku Kogyo Former First Factory (久金属工業旧第一工場, Hisa Kinzoku Kōgyō Kyū Daiichi Kōjō) is a one-story timber workshop in the southeast corner of a bottle-cap maker's head-office factory in Kitatsumori, Nishinari Ward, Osaka City, built in 1934, the year the company moved here, and registered as a Registered Tangible Cultural Property on February 4, 2021.

It measures 24 by 13 meters, a building area of 309 square meters and the largest of the nine registered structures on the site. The sheet-iron gable roof carries a wide raised section along its ridge, a clerestory that lets daylight into the floor below.

The Agency for Cultural Affairs counts it among the principal buildings of the metalworks.

Why the Former First Factory Was Registered

What the Agency singles out in the Hisa Kinzoku Kogyo Former First Factory is the roof framing, which combines a Japanese Wagoya frame of posts on beams with Western-style triangulated trusses. The Agency calls the combination unusual. The formal criterion is contribution to the historic landscape.

The city's Osaka Selection citation also names the timber trusses as one of the site's highlights. The company remarks that the building must have been strikingly large for its day, and that its size has left it exposed to repeated storm damage.

What to Look For: Open Rafters and Steel-Wrapped Posts

There is no ceiling. The roof framing and the sheathing boards above it are left exposed over one large room, with wagoya beams and diagonal truss members crossing overhead.

The company notes that the 5-sun posts, about 15 centimeters thick, have been wrapped in steel for strength. Steel added to a timber frame is the mark of a building kept working rather than replaced.

For years the walls were covered in corrugated iron. In 2020 they were restored to something close to the original finish.

Osaka Cultural Properties Navi and the city both mention that prewar press machines and other machine tools are kept on the premises. Since powered presses drove the company's early growth, it matters that machines and workshop survive together.

Visiting the Former First Factory

The Hisa Kinzoku Kogyo Former First Factory stands deep in the southeast of the compound and is hard to see from the street. The interior is open only when an open-house guided tour includes it, and in 2024 photography was restricted in parts of the interiors.

If you get inside, stand beneath the clerestory and look up. Light from the raised ridge falls on the middle of the floor and picks out the mix of wagoya beams and trusses. At the foot of the posts you can see the steel sleeves that now brace the timber.