Skinny Residential Towers Rise Again

My friends Jeff and Geraldine live a charmed life that we in the trenches can only dream about.  Jeff is a mathematics professor at University of Michigan and has spent the past couple of decades on a circuit that includes summers at their North Michigan cabin, fall semesters teaching at U Michigan, winter terms teaching at the Sorbonne in Paris, and spring terms teaching at the University of Pisa.  Through it all, Geraldine has maintained a very interesting blog, Travel Oyster.

One of Geraldine's posts was on the residential towers of Pisa.  In Pisa in the 1200's, hemmed in by defensive city walls, it was the fashion of wealthy Pisans to construct pencil thin, tall residential towers.  Casa torres.  Galileo lived in one of them and showed the moons of Jupiter to Cosime II de Medici through his newly perfected telescope from the balcony. 

After 60 years of suburban expansion we are migrating back to the cities, and even though we are no longer hemmed in by city walls, space is at a premium and we are once again building tall residential towers.  In San Francisco, at the west approach to the Bay Bridge, the One Rincon Hill tower stands guard over an endless stream of taillights still heading to the suburbs at the end of the work-day.  This luxury tower was completed in 2008 and is now 97% occupied.

 In this Wall Street Journal article, Eliot Brown writes:

In New York, Tel Aviv, Vancouver and other cities around the globe, skinny apartment towers are on the rise, sprouting like luxury beanstalks from small lots—some only as wide as a handful of townhomes.

... While thin towers already crowd the skyline in land-starved cities like Hong Kong, developers elsewhere generally eschewed the slim structures, opting for larger, more stable floors—typically at least 10,000 square feet for tall buildings. But that's been changing lately. In New York, work has begun on the planned tower at 432 Park Ave., designed by architect Rafael Viñoly, that is expected to have approximately 8,250-square-foot floors and is slated to rise to about 145 feet taller than the Empire State Building. Just one block south of Central Park, the 1,004-foot-tall One57—which saw its crane break during superstorm Sandy—is under construction, with floors as small as 6,240 square feet. And the Cetra/Ruddy-designed One Madison Park, a 597-foot tower with 3,300-square-foot floors, is nearing completion.  ....

Building high, of course, gets expensive. As the floor count goes up, steel takes longer to lift and high winds can stall construction. Slender towers need a giant device, called a damper, toward the top to counter sway from wind. Without such features, buildings could rock to the point of making residents motion-sick.

"It's definitely not easy or cheap," said Michael Stern, managing partner of JDS Development Group, which is planning to soon start construction on a 679-foot tower on a lot just 43-feet wide down the block from One57. Rising high-end apartment prices, he said, have helped make such buildings possible.

Technology has also helped give rise to the buildings. For instance, the material of choice for apartment towers, steel-reinforced concrete, is more than twice as strong as a generation ago. Software in engineering offices can much better predict issues like how much a tower might sway, allowing for more efficient buildings with fewer columns.  "Ten years ago, the tools were a lot rougher," said Ahmad Rahimian, chief executive at WSP Cantor Seinuk, a structural-engineering firm that's currently working on at least a half-dozen narrow, tall apartment towers. "It's getting a lot more sophisticated."

Fetching a premium price of up to $90 million dollars for some penthouses, these towers, like the casa torres of old are upscale abodes for the masters of the universe, and living there is something that most of us can only dream about.