A Detailing Mystery

by Don Friedman on January 26, 2018

That picture is looking up at the underside of a floor in an old warehouse. The walls are solid brick, and the floors are concrete vaults supported by steel beams.

The last beam supporting a vault is a channel that runs into the face of the pier just past the window, where it is supported by the big girder (above the left-right portion of the pipe).This leaves a 9 or 10 inch space between the inside face of the wall and the channel, and that space is filled with a brick corbel coming off the wall.

The last time I pointed to a corbel detail like this, it was in a heavy-timber building and was specifically used to prevent hot gas from rising from one floor to the next during a fire. It’s less clear what’s going on here. A few possibilities:

  • Since there’s no way to cantilever a portion of concrete vault past the last beam, the corbel was used to close off the opening in the floor. But then why not shift the last beam so that it’s tight to the wall?
  • The building was constructed as heavy timber and later upgraded to steel and concrete, and the corbel is a carry-over.
  • The building was planned as heavy timber and switched during construction to steel and concrete, with the corbels already built.

There are probably more possibilities that don’t occur to me just now. And, as usual, it’s unlikely that I’ll ever know the answer.

A Slight Exaggeration

January 20, 2018

Those are the columns at the first floor of a seven-story concrete-frame industrial. building from the 1920s. They are roughly three feet in diameter and spaced at twenty feet on center. When that percentage of floor area is occupied by columns, they are intrusive and affect everything that might be done with the space. If […]

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Light Underground

January 17, 2018

That’s a vault light by the Luxcrete Company of England, a descendent of the Luxfer Prism company. As cool as the lenses are, I love the brass letters set in the concrete.

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A Fine Line

January 10, 2018

That’s an old picture of the Cleft Rock Bridge in Prospect Park, built in 1872 as one of the picturesque bridges that Olmsted and Vaux liked to use for grade separations in park designs. It’s a nice looking bridge, although not remarkable within O&V’s work. What makes it remarkable is that it’s not cut stone […]

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January 8, 2018

That’s the ceiling – which appears to be the structural roof – at the north entry to the Whitehall Street station on the R/W. Specifically, this is the stair leading down from the entry mezzanine to the platform. The excavated volume of space is a sloped rectangular prism, with the roof following the slope. The […]

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Three Myths About Brutalism

October 25, 2017

Neave Brown, the architect of the Alexandra Road housing estate in London (above, click to enlarge) as well as other brutalist housing projects, has recently been recognized for his work. In architectural terms, this is undiluted brutalism, with nearly all exterior surfaces as bare concrete or glass. The article at the second link above summarizes […]

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A Concrete Building

October 11, 2017

A market hall in Wrocław, Poland: That’s how you do exposed concrete. The hall has the basic layout of a church, with a cross plan for the high gable roof and lower infill between the cross arms. The roof and its clerestory are supported by a series of parabolic concrete arches, which intersect at the […]

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What Is A Building’s “Material”?

October 10, 2017

Curtesy of Marcin Wichary: I’ll almost certainly be getting this map of “Concrete New York” but I find the discussion on Curbed to be problematic. In my opinion, New York does not have an iconic city-center concrete building the way that (among others) Boston, Chicago, and Washington do; the best concrete building nearby has been altered […]

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Patterns of Damage

September 28, 2017

João Carlos Souza has a primer up on ArchiNet on how to identify problems in concrete buildings based on crack patterns. Putting aside some bad translation from Portuguese to English* it’s quite good and can help identify damage when used as intended. Mr. Souza does not explicitly state the assumptions that went into his visual […]

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Anna Karenina in Concrete

September 10, 2017

Tolstoy said that “Happy families are all alike; every unhappy family is unhappy in its own way.” This principle can be applied to buildings: every building in good condition is alike, every failing building fails in its own way. The white paint on the concrete does a great job, in my opinion, of highlighting where the […]

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