Sustainable construction for a single-storey school
The school is single-storey and triangular in plan, providing generous classroom spaces by rationalising circulation; internal rooms are naturally ventilated by underfloor ducts - and lit with rooflights.
Low-energy, sustainable materials are used. The external 'breathing' walls consist of 225mm timber stud frames filled with Warmcell insulation and lined with a double skin of plasterboard on the inner face and Panelvent sheathing on the outer face, clad with t & g cedar boarding, chosen for low maintenance. Internal walls are of loadbearing blockwork.
The roof, an Erisco-Bauder 'green' roof comprising a vegetation blanket, filters and drainage membranes, has perimeter drainage strips which run to downpipes. It is laid on an insulated ply deck resting on 400mm deep Masonite joists; in span they range from 6m to 12m. The roof cants upwards to admit rows of vertical rooflights. A low-maintenance ceiling is formed of full-size beech-faced plywood sheets fitted with recessed lighting.
To organise windows of differing sizes into a cohesive elevation, a 'plimsoll line', a band of 19mm marine ply, 1200mm deep and in the same plane as the cedar boarding, runs along the south, west and east elevations. The plywood is stained dark grey with a water-based stain to match the dark grey polyester powder-coated aluminium composite timber window frames. The windows are set back from the plane of the cedar boarding and framed with19mm ply liners, protected with aluminium drips at head and sill. The eaves have a strong 300mm deep edge provided by a dark grey aluminium coping.