200 Clarendon (John Hancock Tower) - tallest building and early window failures

200 Clarendon Street (the John Hancock Tower), completed in 1976 and designed by I. M. Pei, is the tallest building in Boston and in New England. Shortly after its completion the tower experienced problems with large glass windowpanes failing and detaching during storms, prompting a full replacement and remediation program; the building’s wind and sway behavior also led to additional engineering work. The tower’s construction issues and eventual remedies are well documented in engineering and architectural histories of Boston.