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Sir Robert McAlpine has started construction of a complex roof structure at Gradel Quadrangles for New College Oxford.
The Gradel Quadrangles project involves the creation of a three-storey quadrangle of student accommodation, new school buildings, porter’s lodge, and a 21.5m tower. It will feature a complex limestone and sandstone facade.
Originally, the main quad building was to have a sprayed concrete roof. But McAlpine redesigned the roof with its architects and structural engineers in a bid to make it more cost effective, taking a low-carbon approach.
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It explored six alternative construction types and 15 different coverings. Eventually, it agreed with the college to replace the original design with a glulam timber structure with tessellated aluminium tiles.
The redesigned roof is cheaper to build, delivers a three-month programme reduction, and minimises embodied carbon.
