porous

I. The warehouse

Takanezawa is a town of about thirty thousand in Tochigi prefecture, north of Tokyo. Near the station there used to be an abandoned rice storehouse built of Ōya stone — a whitish volcanic tuff quarried not far away, soft enough to cut with hand tools, full of pores the way pumice is. The deposits formed fifteen million years ago in a submarine eruption. Storehouses around Utsunomiya have been built from it for centuries, warm and gritty and the color of cooled bread crust.

In 2006 Kengo Kuma’s office finished a small community hall on the site. The brief, briefly: keep the warehouse. Don’t demolish, don’t restore, don’t replace. Take the existing Ōya and re-stack it next to and around the old block, paired up, woven together with thin steel plates set on the diagonal. The stone holds the load; the steel does the geometry. The two materials make a basket and the basket makes the wall.

The wall is half stone and half air. The Ōya was always porous, and the diagonal weave preserves that — light comes through. Inside the new hall the old storehouse stands as the original block, and the new structure is its lighter cousin, made of the same matter and looser logic. Chokkura Plaza, they called it. A storehouse with the lid taken off.

II. The station

Two years later, the same office, the same town. Hōshakuji Station — open since 1899 — was rebuilt around its east-west axis. The town had been split by the railroad: two halves, no easy passage between them. The brief was to open an east exit and let the two sides see each other.

Lauan plywood, this time, not stone. Where Chokkura had the basket-weave of stone-and-steel, the station has diamond lattice — three-dimensional triangulated wood overhead, panelling the corridors and stairs in soft brown grids. Same diagonal logic; lighter material. Kuma’s note on the project uses the word “pore.” The point of the station, he writes, was not to be a building. The point was to be an aperture wide enough that two halves of a town could move through each other.

It won the Brunel Prize for railway design in 2008. The town now has two Kuma buildings about reconnection — one about the warehouse it almost lost, one about the railroad that had been splitting it for a hundred years.

III. Diagonals

What both buildings share is the diagonal member. Walls in compression and tension at once. Materials that were porous on their own — volcanic tuff, plywood end-grain — held together by woven lines rather than poured slabs. Neither building is heavy; both have visible air in their walls.

Civic architecture mostly does the opposite. Town halls and stations are meant to be massive so they can be authoritative; their walls separate, enclose, weatherproof, intimidate. Kuma’s two Takanezawa buildings refuse that posture and use thin lines on the diagonal to make a fabric instead of a fortress. People go inside not because the walls keep weather out but because the basket is wide enough to catch light and people both.

A small town in Tochigi with thirty thousand residents has more well-made apertures per capita than most cities. They were both made on purpose.