Sure, it's a subjective question. Where I live, it's anything taller than four stories, at least in the local media's eyes. But from a real estate perspective, there really is a minimum number, and they are being built in record numbers in the U.S.
Conor Dougherty writes from Minneapolis where he describes one of two new luxury residential high-rises set to open in downtown in August. The Nic on Fifth, a "26-story apartment building that sits smack on a light-rail stop and boasts amenities like a pool deck and a private dog park," is representative of what is becoming increasing more common throughout the U.S. (though I'm not sure how many of these towers can boast private dog parks).
For more information on this transit oriented development, see "The Nic on Fifth Brings Luxury Living to Minneapolis’ Nicollet Mall" by The Opus Group.
Axiometrics, a Dallas apartment-research firm, defines a tower as 15 stories or more, writes Dougherty.
This year, some 74 rental towers are on pace to be completed, and there are 81 on the books for 2015—the highest number since at least the 1970s. At the same time, strong apartment rents and sluggish demand for office space have resulted in some high-rise buildings being converted to apartments. [See chart showing 2005-2015 data].
Dougherty writes that while the high-rise residential towers are more likely to be built in "denser and pricier markets like San Francisco, New York and Chicago, (b)ut in percentage terms, the increase has been most dramatic in smaller cities like Minneapolis, which is building apartments, including high-rise apartment buildings, at the fastest pace in decades."
"It's the Manhattanization of America and it's happening in cities that never had rental high rises," says Mark Humphreys, chief executive of Dallas-based Humphreys & Partners Architects, which specializes in apartments and condominiums.
Going back to the suburban cities that I'm familiar with in the Bay Area, residential opponents, even judges at times (e.g. Redwood City, Calif.) would appear to decry almost any multi-family new development, regardless of its height, as a symbol of the "Manhattanization" of their city. Could that loaded term be taking on a new, more positive meaning?
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City of Albany
UCLA Lewis Center for Regional Policy Studies
Mpact (formerly Rail~Volution)
Chaddick Institute at DePaul University
City of Piedmont, CA
Great Falls Development Authority, Inc.
HUDs Office of Policy Development and Research