Dating from the 1950s, the school complex is laid out around a courtyard space that has now been closed off by the new sports hall. The floor of this tract was sunk below site level, so that the large volume of the hall rises by no more than a single storey above the ground. In addition, extensive areas of glazing create visual links through the building. The 45 x 25.50 m roof structure is in steel and timber, with a series of raised, cubic, northlight lanterns that ensure an even daylighting level internally. Six laminated-timber main beams span the width of the hall at 7.50 m centres, forming the closed faces of the north-light structures. The beams are supported in the facade plane by tubular steel columns that also house the rainwater pipes. Together with the main beams, Z-shaped secondary beams – spaced at 6.40 m centres and consisting of welded steel I -sections – form a rigid structural system. Lateral bracing is provided by the roof construction and by the raised lanterns.