A toroidal shell roof covered with rainscreen and glazed panels
Two concert halls and a rehearsal space are covered with a toroidal shell roof approximately 100m x 100m. It fits closely over the three main spaces in a form based on intersecting toroidal surfaces.
The structure of this complex shape is formed from standard radiused steel components.
The four primary roof arches are formed from radiused 838 x 292mm UBs with secondary members of radiused 406 x 178mm UBs spanning between the arches at approximately 4m intervals.
The structural grid shell of the roof is completed by tertiary members -168.3mm diameter CHS beams and 30mm diameter solid steel crossbracing rods. They combine to stiffen the roof and allow smaller, secondary members to be used. To make the roof more economic, simple bolted connections are used where possible.
The roof structure is clad to form a smooth flush skin of solid and glazed panels.The major part of the roof is clad with stainless steel rainscreen panels over a built-up roof system. It consists of a trapezoidal-profiled steel deck, rigid insulation and single ply membrane, overclad with stainless steel rainscreen panels.Rainwater drains through joints in the rainscreen panels to the membrane below and follows the slope of the roof to its valleys, where a gutter directs it into downpipes.
Panels of double-glazed units in anodised aluminium frames, faceted at their edges, are fixed to projecting tapered brackets to lie in the same plane as the stainless steel panels.The brackets are bolted to the secondary beams at approximately 2metre intervals. Solid steel suspension rods 25mm in diameter carry the weight of the panels back to the main roof structure.