Satake Glass Workshop

Where the Rods Are Made

The Satake Glass Workshop (佐竹ガラス作業場, Satake Garasu Sagyoba) is a single-storey timber factory building of the early Showa period in Saiwai 2-chome, Izumi City, Osaka Prefecture, used for making glass rods and entered on the national register as a Registered Tangible Cultural Property on April 24, 2001.

It sits at the back of the premises of Satake Glass, a maker of colored craft-glass rods founded in 1927, adjoining the east side of the melting plant. The plan is L-shaped, the roof is laid in Sangawara-buki pantiles, and at 495 square metres it is the largest of the six registered buildings.

The official description says the Satake Glass Workshop occupies the inward-facing part of the compound. If the main house and melting plant are the face the property shows the street, the workshop is the back room where the work is absorbed.

Why It Was Registered

The Satake Glass Workshop was listed as a building that contributes to the historic landscape. The Agency for Cultural Affairs points to an exterior that harmonizes with the whole and to its role in shaping the inner part of the property.

At Satake Glass, the relationships between buildings are the point. By filling the back of the lot with a single 495-square-metre L, the workshop closes the ensemble: house, office, melting plant and mixing factory become one enclosed compound rather than a row of separate structures.

The listing is about appearance, but it is worth remembering what goes on inside. Of the six registered buildings, the Satake Glass Workshop is the one where the product itself takes shape.

What to Look For: Braced Posts and a King Post Truss

The Satake Glass Workshop is most interesting on the inside. According to the official description, each post carries diagonal braces on all four sides, and the posts support a King post truss roof. The braces stiffen the joints between post and beam and help keep the frame from racking.

A king post truss is a Western roof frame built from triangles around a central vertical post. Here it sits beneath a tiled Japanese exterior. The description adds that the framing is the same as in the other factory buildings, so this is the shared structural system of the Satake Glass works.

The L-shaped plan is worth noticing too. The wing turns at a right angle from the melting plant and runs deeper into the lot, a layout that reads as a way of fitting both floor area and a working sequence onto a tight urban site.

Visiting the Satake Glass Workshop

Because the Satake Glass Workshop lies at the back of the property, it is hard to see from the street. The interior is a working shop floor and is not open for casual entry.

Satake Glass runs factory tours by reservation, and the Kansai Bureau of Economy, Trade and Industry notes that visitors can see the rod-making process. Which buildings a tour enters depends on the day's work, so if you want to see the workshop's roof framing, say so when you book. Production is sometimes not on view because of furnace or scheduling issues. Ask about photography at the same time.