A sinuous 'waveform' metal deck roof, 12-15m above the ground, oversails the theatre and arts building. It is an insulated metal deck covered with a Sarnafil membrane; the curve is formed by 610mm deep universal beams. At the north end of the building, where the main entrance is located, the beams taper and crank upwards at their ends, and are supported on eight 2.25m long cast in-situ fins, 650mm wide at their centres with a glass curtain wall between them.
Visitors pass through a glazed lobby to enter the foyer, a 12m three-storey high space containing staircses which lead to upper levels of the theatre.
The glass curtain wall system consists of large panels of double-glazed units, 4.4m high and 1700mm wide, framed in millfinish aluminium and suspended from the roof structure.Too large to be toughened in the UK, they comprise two sheets of 10.8 and 8.8mm laminated glass.
The glass wall is braced at lobby roof level by a row of bowed horizontal trusses bolted at their end to the concrete fins. Each truss consists of a 219mm diameter CHS welded to Ibeams with solid bars and CHS struts; the bowed shape reflects the bending moment. Fixed to the trusses are a series of 'ladder' supports - each a 114mm CHS welded with 300 x 300mm steel plates to paired steel plates - which support the glazing mullions.A heating element runs within the truss to eliminate condensation.
The lobby is glazed with toughened glass jointed with silicon. It is divided on the inside by an aluminium fin which houses services and the sliding door mechanism.