Lever House, 390 Park Avenue, New York (Gordon Bunshaft, 1952).
Lever House, a glass box built for the famous soap manufacturer, is one of the most important commercial buildings of the 20th century. It was the first international-style skyscraper in Manhattan; it made its architect, Gordon Bunshaft, famous; and it established his firm, Skidmore, Owings, and Merrill, as the place to go for sleek, clean-lined, prestige architecture.
The cool colors of the exterior curtain walls (mere cladding on a steel frame) with crisp aluminum mullions gives the building a light feel, as compared to the stone-clad behemoths of the Art Deco era such as the Chrysler Building. This is notable, and very successful in this building, but not revolutionary--Pietro Belluschi's Equitable Life Assurance Building in Portland, Oregon (1944-1947) had already done something quite similar and arguably more attractively. Where Lever House strongly breaks with tradition is in its massing. The vertical slab rises over just a fraction of its lot: why not be more efficient, as Belluschi had been, and build out to the property lines?
The answer lies in the ownership of, and right to, light and air. New York City planners had long since seen how terrible and inhuman urban streets could be when bordered by "steel canyons" of skyscrapers. You could go all day without any sun in some parts of the city. The concept was developed that each lot had a right to a certain amount of air and light, and after 1916 architects were barred from building such as to obstruct either within certain limits. For this reason, Art-Deco-era skyscrapers attained their characteristic form with setbacks as the building grew higher; higher floors had to have a smaller plan so as not to obstruct unduly the air and light rights of neighbors.
Bunshaft erected a one-floor horizontal mass on pilotis, and this mass covered the whole lot, though it was perforated in the center to let in light for the garden and open pedestrian walkway underneath. The vertical slab rises cleanly, with no setbacks, for 24 stories. The price of its clean lines was that its footprint could only occupy a portion of its lot. This was the true revolution. (Mies's Seagram Building across the street carried this trend a step further a few years later.)
Still, the glass facade is beautiful and impressive. It allows one to see the physical structure of the building (its steel framework visibly rising through it, its members spaced 6 windows apart), and impressed those used to grime-coated urban stone buildings with its physical cleanliness (the building gets a thorough scrub every 6 days) and transparency at night. The thin aluminum mullions (window frames) which articulate the face of the building are crisp and accentuated in the vertical, reinforcing the dominant characteristic of the slab, which springs up lightly. Unfortunately, the adjacent lot to the north received a frightful imitation by an inferior architect which spoils some of the effect in modern photographs (and to the eye).
Lever House represents an important moment in American architecture, a masterpiece by an architect in his prime which was a watershed for subsequent buildings all over the world.
http://www.greatbuildings.com/buildings/Lever_House.html (Multiple photos.)
http://www.som.com/resources/projects/2/1/5/printPreview.html (SOM on Lever House.)
http://go.supereva.it/newyorkcity2/vostre-foto.htm?p (Chrysler Building: imagine it without setbacks!)
http://www.greatbuildings.com/buildings/Equitable_Building.html (Belluschi's Equitable Building.)
Khan, H.-U. 2001. International Style. Modernist Architecture from 1925 to 1965 (pp. 130-132).
Kidder Smith, G.E. 1996. A Source Book of American Architecture. 500 Notable Buildings from the 10th Century to the Present (p. 408).
LeBlanc, S. 1996. 20th Century American Architecture. A Traveler's Guide to 220 Key Buildings, second edition (p. 93).
Morrone, F. 1998. The Architectural Guidebook to New York City (pp. 167-169).
Willensky, E., and White, N. 1988. AIA Guide to New York City, third edition (p. 249).