Big Data, Facade Version

by Don Friedman on May 23, 2017

The New York City Department of Buildings has a fascinating web page up that uses statistical analysis on the thousands* of facade inspection reports that are filed on a five-year cycle under the Facade Inspection Safety Program**. Here are a few of the facts that are clear, either directly stated or can be inferred from the data:

  • There are some 14,000 buildings in New York that are seven stories or more high.*** There are roughly a million buildings in New York, so only about 1/70 of the buildings in the city are seven stories high, which is a good cut-off for “mid-rise” height. Why so few? Because a lot of the city consists of free-standing houses (mostly in Queens and Staten Island), brownstone and other rowhouses (mostly in Brooklyn and Manhattan), tenements (mostly in Manhattan and the Bronx) and low-rise commercial buildings all over.
  • The number of seven-story or higher buildings is roughly the same in Brooklyn, the Bronx, and Queens. I would not have guessed that. My mental image of Queens, despite having grown up there in a seven-story apartment house, is block after block of two-story free-standing houses.
  • The combination of ordinary aging of facades and repair work has led to a steady state condition. There are currently three possible reported states for a facade upon inspection: safe, unsafe, and safe with a repair and maintenance program****. If you compare cycles 5, 6, and 7 (the most recent that is complete), the percentage of safe buildings is about the same, and the percentage of SWARMP facade has decreased only slightly. Basically, in the most recent cycle, a small percentage of the buildings that might previously have been classified as SWARMP are now classified as unsafe. The classification system was a bit different for cycle 4 and earlier, bit if we add the old class of “ongoing maintenance” to the SWARMP and we add the old class of “ongoing maintenance” to safe, we get again pretty much the same percentages.
  • The general climate of facade repair is working. A building marked as SWARMP automatically becomes unsafe in the next cycle if repair work has not been performed. so the 40 to 50 percent of buildings that have enough damage to be classified as SWARMP are getting fixed or else the percentage of unsafe buildings would have skyrocketed.


* Per the graphic, currently at more than 14,000 buildings per cycle, and we’re in the 8th cycle.

** Formerly known as Local 11; before that, known as Local Law 10.

*** Buildings six stories or lower are not subject to FISP inspection.

****AKA SWARMP, possibly the worst acronym I encounter on a regular basis.

The Engineer’s Eye View

May 22, 2017

I took that picture last summer, while performing a facade inspection from a telescoping hydraulic lift. The right side of the picture is the last section of the arm, with the joint in the lower right the connection from the arm to the bucket; the white section of arm vertically in the center is the […]

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Review of “A Taste of New York”

May 21, 2017

If you suffer from vertigo, you might want to skip this one. It’s fun. I wish the film-makers had included some more footage outside of the most famous Manhattan icons, but then again, I know exactly where on the 7 train they were for their one shot in Queens, so maybe I’m not the target […]

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Jurassic Silliness

May 20, 2017

I’m not sure Jurassic World needed structural analysis, but it’s got it now.

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Steel Trusses and Wood Purlins

May 19, 2017

No deep thoughts today, just appreciation for a well-designed roof. It’s an industrial building so finishes were kept to a minimum, and there was no requirement for fire-rating. The trusses are steel because they span about 50 feet; the purlins span 18. The end bays have diagonal rod bracing in the plane of the truss upper […]

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Partial Technology Transfer

May 18, 2017

William Gibson once  wrote “The future is already here — it’s just not very evenly distributed.” That’s true now and was also true in the past. Just because something new and useful has arrived on the scene doesn’t mean it’s everywhere and doesn’t mean it’s being used in its “modern” form everywhere. The picture above […]

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A Change In Perspective

May 17, 2017

That’s “The Rush Hour, New York City” by Colin Campbell Cooper, painted in 1906. The view is south, across the northeastern tip of City Hall Park. The tall tower on the right is the Park Row Building, the two buildings flanking the narrow street in the center are the old New York Times building on the […]

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Pragmatic Concrete

May 16, 2017

That strange-looking pier above requires some back-story explanation. The New York subways were originally built as three systems – the privately-owned IRT and BMT, and the city-owned IND – which were organizationally integrated in the 1940s. The IRT and BMT were competing with each other but were also joined at the hip by an expansion […]

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May 15, 2017

These photographs of the demolition of the Orange County Government Center designed by Paul Rudolph are heartbreaking even if brutalism isn’t your favorite style. It was an uncompromising expression of a never-popular style and, because it required non-standard detailing and repairs, it was not well maintained and had severe problems with leaks. Ultimately, there was a […]

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Research Dots

May 14, 2017

The New York City Landmarks Preservation Commission has created a nice tool: an interactive map of the city’s designated landmarks with information about the buildings and sites. The distribution in the broadest view also gives, somewhat accidentally, some information about social history. The map of the Bronx above shows a lot of landmarks west of […]

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