A ROOF WITH VALLEY GUTTERS AND A SUNSCREEN
The primary school, T-shaped in plan, consists of a two-storey entrance/administration block facing west which extends into a single- storey classroom block facing north and south, with classrooms on both sides of a central mall. Each classroom has its own store and wc, with large opening windows and a door giving access to play areas.
The school roof is - in the architect's words - a 'gull-wing' roof: a series of shallow pitches covered in profiled colour-coated aluminium sheet which end at the north and south eaves in an upward slope like delicate oversailing 'wings'.
At the eaves, 175 x 50mm joists project beyond the roof covering, their end-grain protected by a lead cap. At the valleys the joists are connected to paired 405 x 90mm glulam beams which support broad valley gutters. The valleys run along the classroom block in an east/west direction; two at the centres of the classrooms and one above the mall, where the glulam beams are supported on paired glulam columns.
The gutters are made of 18m ply lined with Sarnafil on 100 x 100mm angle framing. The roof joists on each side are connected to the glulam beams by a 127 x 76mm universal beam which acts as a spacer and tie member.
The glazed walls of the classrooms are shaded by a series of sunscreens. A clerestory above the sunscreens is set back to allow daylight to penetrate deep into the classroom.
The sunscreens are fabricated from 75 x 8mm-thick galvanised steel fins welded into a steel grillage which cantilevers from a pair of 152 x 150mm universal columns. A 76mm chs tube is welded to the outer edge of each screen to which the suspension rods are fixed. The assembly is fully adjustable to allow it to be aligned precisely after erection.