Wilkinson Eyre Architects
A steel solution has allowed the construction of an 18 storey commercial development on top of an existing raft foundation originally designed to support a smaller building. Designed to achieve a BREEAM 'Excellent' rating, the building will provide 16 floors of Grade A office space, plus two upper levels for plant equipment.
Below ground, the structure is founded on an existing three level reinforced concrete basement raft - a feature that has had an overwhelming impact on the design and construction of the tower. The raft was constructed in 1982 for a previous development, with the majority of the lower two basement floors assigned as its canteen and office storage. As the raft was in use it had to be retained and incorporated into the design, so a framing material for the new building that could be safely and quickly erected above functioning office space was needed.
A steelwork solution was the answer, as the material not only helped the contractor to build over RBS's subterranean facilities, it also allowed the new structure to be considerably higher than the one originally proposed. Steelwork's lightweight attributes consequently allowed the construction project to achieve its aim of increasing office space while incorporating an existing basement. A steel frame supporting metal decking offered the solution and the fact that the steel trusses could be quickly erected over RBS's delivery road at night meant that there was no disruption.