The Royal Insurance Headquarters now the Royal Sun Alliance Insurance Building is a massive, irregular ziggurat. Faced with ribbed concrete and aggregate panels, the heavy massing of the building is punctuated by slit windows (designed to maximise energy efficiency) giving it a fortress allusion.

Built between 1974 and 1976, architects the Tripe and Wakeham Partnership created for Royal Insurance an intelligent interpretation of a complicated brief, filling a large 2.8 hectare site with two stories of car parking (as a podium), placing large departments and circulation spaces on top, with additional functions placed higher up as separately readable volumes. The impression created is one of an exceptionally well arranged kit of individual rectilinear blocks. The rough texture of the ribbed panelling provides the piecework of thrillingly blank walls, but the bouncing interplay of solid and void provides the real interest. As the volume of the structure generally recedes up the storeys, buildings within buildings reveal themselves as a series of terraces breaks up the considerable bulk into the striations of a ziggurat. Matthew Whitfield The Modernist issue 3 ‘BOOM & BUST’

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