Sports Hall in Bietigheim-Bissingen

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 25.50m roof structure is in steel and timber, with a series of raised, cubic, north-light lanterns that ensure an even daylighting level internally. Six laminated-timber main beams span the width of the hall at 7.50m 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 6.40m centres and consisting of welded steel Å-sections – form a rigid structural system. Lateral bracing is provided by the roof construction and by the raised lanterns. Channel sections between the Z-beams offer further resistance to compression forces in the transverse direction, while in the longitudinal direction, this function is performed by hollow steel sections along the peripheral axes. White-glazed prefabri-cated timber box elements were inserted between the Z-beams to create a smooth soffit that appears to float between the lantern structures. The high degree of prefabrication ensured a swift erection process.