Grids like this are typically welded together on-site. For the London arcade, however, the complete roof structure was delivered ready to assemble and bolted into place. The accuracy required in the length of the lattice struts of 2/10mm corresponds to a tolerance standard that is typical in engineering. The thickness of the struts varies depending on the structural requirements. This design kept the outer cross-section profile consistent, producing a precise, uniformly sized grid. All the nodes are unique. They are composed of 20 individual parts that are welded together and precisely milled for angle and size on a CNC milling machine. 60% of the surface consists of thermal insulation panels, and the remaining area is double-glazed. The roof panels are arranged so that the glazed areas are shaded when the sun is low. The triangular roof panels are placed on the grid structure with sealing strips, clamped with two point fittings on each side and wet-jointed.
Images: © seele / Matthias Reithmeier
