Masonry

Form Follows Function

by Don Friedman on November 19, 2017


The 1896 window sill in the picture above may be the most perfectly designed piece of architecture in the city. It’s there to provide a base for the wooden window frame, to protect the relatively porous brick from water infiltration from above, and to shed water. It had to be built into the solid brick wall and installed by ordinary masons.

The center of that piece of stone has a five-sided cross-section: a rectangle with the outer top corner nipped off at an angle. The ends are the full rectangle, without the angle; the transition from four-sided to five-sided cross-section is handled by another angled face. The entire piece is 8 inches high, so it fits in the space of three courses of brick, and the whole is twelve inches deep so it fits across the thickness of the three-withe wall.

That oddly-shaped stone meets every requirement and has performed perfectly for over 120 years with no repairs. I challenge anyone to find a way to improve it.

Arching Action Index

October 31, 2017

I’ve been caught up in writing about arching action recently, and I thought it might make sense to collect all of the posts on this topic in one place. So: What Is Arching Action? Arching Action, Too Not Amenable To Easy Analysis Arching Action Visible Jack Arches Are Arching Action If I post again on […]

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Physically Impossible

October 31, 2017

That’s the north facade of 390 Fifth Avenue, the Gorham Building, at its east end where it meets the Fifth Avenue facade. It was built in 1906 and the avenue storefronts were modified in the late 1960s or early 70s. Where the newer glass curtain wall ends, just to the left of the truck, you’ve […]

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Telegraphing Through

October 20, 2017

Another artistic photo, this time of one face of a party wall in a rowhouse. If you look closely (click on the picture to expand it), you’ll see that the plaster is well-adhered to the brick. The plaster didn’t fall off in that one area, it was removed. Why? Because the presence of that long, […]

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This Is Ungood

October 18, 2017

From a few years ago, some rotting wood beams and a failing brick pier. In 1989, I performed a long and difficult site visit to check on a structure I won’t name (confidentiality is still in place, even after all these years) that had to be reviewed once per year. The fellow who had been […]

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Road Trip: An Orphaned Wall

October 16, 2017

Seen on the street in Ottawa… I’ve mentioned orphans walls once before. They are what’s left when old walls are incorporated into new buildings in a manner that makes it difficult or impossible to demolish the wall when the original building is demolished. In this case, the light-red wall with white trim obviously belonged to […]

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Intentionally Tilted Masonry

October 6, 2017

That’s a photograph taken in an attic of a mid-1800s house. The good news is that the wood is dry as a bone, so it’s not rotting. The maybe bad news is that brick chimney…isn’t quite straight. The reason for the chimney running diagonally is, simply, fakery. The fireplace below didn’t, for whatever interior layout […]

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Inverted Arch Foundations Are Upside-Down Fun

October 5, 2017

Every once in a while during design, I remind myself of what various types of structural member do, as a way of thinking about what I need done. For example, the simplest definition of a “beam” that I can come up with is “a linear structure that carries load at right angles to its long […]

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Blatant and Odd Fakery

October 4, 2017

The entrance to a garage in a late-1980s, maybe early 1990s apartment house is dead center in that photo. I can’t stop staring at the “flat arch” above the opening. Someone went to a lot of trouble to make the stone veneer (which is most likely in front of concrete block back-up) look like this […]

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Rising To Failure

October 3, 2017

This is the same building as the unlinteled door – it was chock full of bad masonry conditions. The picture above is just to provide some context. I’m interested in the brick pier in the cellar. Here it is in isolation: There are several possible causes for the visible damage, but rising damp is the […]

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