Following the opening of the blocky and (for the time) astronomically tall 41-story
Equitable Building in
1915, New York City's zoning laws were changed in 1916, requiring setbacks on the upper
floors of tall buildings to provide more light at street level and reduce shadows.
This seemingly minor change would have a dramatic architectural impact on the
appearance of the NYC skyline up through the middle of the century. Setbacks
also fit seamlessly into the vertical orientation of Art Deco and the
"Wedding Cake" style would become a defining characteristic
of Art Deco architecture. Completing the phallic symbolism, many Art Deco
buildings have rounded cupolas.
This stairstep design was also incorporated into other vertically-oriented
structures.