Check Out the Condos Being Built On the Roof of a Historic NYC BuildingS

361 Broadway, a cast-iron building in lower Manhattan, has stayed put as the neighborhood around it transformed its factories and workshops into restaurants and high-end boutiques. Now, after 133 years, it's changing too—thanks to two $15 million metal penthouses due to alight on its roof.

The project is being designed by Japanese architect Shigeru Ban, who also did the Metal Shutter Houses in Chelsea. As The New York Times detailed this week, Ban's plan involves building a structure inside a structure, so as not to disturb the landmarked building's historic facade. Inside, there'll be luxury condos—par for the course in this neighborhood—but up top, things are more exciting: Two (also hugely expensive) penthouses built on 361's existing roof, with a massive overhang supported by Vierendeel truss—which will make it possible to open up the entire side of the building to the outdoors:

Check Out the Condos Being Built On the Roof of a Historic NYC BuildingS

It's a cool project—and though it's far from the first time a hungry developer has gone so far as to add floors to an existing building, it's one of the best variations on the theme I've ever seen—despite the sad reality that 99.99 percent of normal New Yorkers will never get to enjoy it.

361 has seen a lot of history since it was built, in 1881, by an architect named W. Wheeler Smith. It's one of the largest cast-iron buildings in the city, and it's housed everything from the textile trade to the offices of Scientific American (you can check out an awesome Landmarks Commission report here). Ironically, we tend to think of these cast-iron buildings as iconic, as great pieces of craftsmanship—but at the time, cast-iron construction was widely criticized, since it was seen as a cheap, imperfect method of faking the style of ornately-carved stone buildings.

361 was a workhorse of a building—built to house business, pure and simple. So while you could whine about how developers are cannibalizing NYC history, the building's 19th century textile baron owners probably would've appreciated the sheer financial genius of the plan. [New York Times]