The boom in apartments buildings

With the housing crisis home-ownership has dropped in the US, the number of renters increased. Rental apartments became the preferred investment option for residential developers. New apartment buildings spring up in many places, even in still shrinking cities. No longer is this building type (British: flats) a limited to affordable housing or luxury condominiums. Now more often than not it stands for "market rate rental". The housing crisis isn't the only driver of this trend, though. Other factors include:

The Millenial generation rediscovered urban life
Increasing fuel cost makes sprawl housing more expensive
Changes in the International Building code allow up to four floors of wood "stick-build" framing on top of a concrete podium. This change brought the economical construction technique previously only used for "walk-up" garden apartments and townhomes to the elevator building, previously a domain of steel and concrete construction.
Zoning: For most of the century, zoning separated uses neatly and ensured homogeneous building types: Residential here, commercial there, industrial relegated to undesirable spaces, retail mostly in the suburbs. Lately, this model has fallen out of favor as anti-urban. Now "mixed use" is in, "place making" and "form-based" zoning all favoring community over set-backs and separation of functions.
"Adaptive reuse", the recycling of old lofts and industrial buildings and increasingly also "Class C" office buildings for residential use is going strong wherever those obsolete buildings are available.

Only foreign cities such as Paris or Berlin had apartment buildings en masse. (And New York, of course). We liked the urbanity of these places but were glad we didn't have to live stacked up like that. Cities like Washington DC, Philadelphia, Boston or San Francisco accommodated most everybody in rowhouses. Apartment buildings that were not public housing existed, but they sat like foreign objects in small clusters or isolated spots. Newer cities like Los Angeles, Denver, San Diego or Austin consisted mainly of single family homes even near downtown.

Baltimore's remarkable apartment buildings could be counted on one hand. There was the early 20th century Beaux Arts Marlborough Building for "old" and ornate" and Mies van der Rohe's 1964 Highfiled House for modern architecture, and the Tindeco apartments stood for cool adaptive reuse.

The once famous Beaux Arts Marlborough
Apartments in Baltimore where the Kohn
sisters amassed the Expressionist
art collection (Photo: ArchPlan)

The 1964 Mies van der Rohe Highfield House in Baltimore
(Photo: Creative Commons)

the Tindeco Apartments in Baltimore, a conversion of an old can factory
with the also converted Canton Cove building to the right (Photo: Real.com)

Boy, have times changed!

Housing and Community Development

1. The boom in apartments buildings

The Renaissance of the Apartment Building