30 Cannon Street, City of London, United Kingdom. Architect: Whinney, Son & Austen Hall , 1977.

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30 Cannon Street was originally designed as an office for Credit Lyonnais. The façades are characterised by tiers of repeating arched white frames around recessed windows of bronze-tinted glass, with each tier separated by a black granite string course which incorporates hidden drainage. The cladding units are pre-cast double-skinned 1.5 metres wide modules of glass fibre reinforced cement (GRC), using a mixture of Portland cement with 5% alkali-resistant glass fibre as reinforcement. It was the first building in the world to be entirely clad with GRC panels. Triple-width modules on the ground floor 4.5 metres wide have two canted windowpanes meeting at an angle, with similar modules repeated on upper floors to either side of the entrances. The slim profile and light weight of the GRC panels allowed the architect to slope the walls outward at an angle of five degrees, with each floor slightly larger than the one below, creating extra square metres of office space. The units of the partial upper floor are inverted, creating a roof line that resembles a crown to the north side and at the eastern end; a roof deck occupies at the south-western corner. Railings on the street have shapes similar to the cladding panels. Grade II listed