Straight and smooth curved Kalzip aluminium standing seam and galvanised liner sheets have been used for the weatherproof envelope of the Influenza Resource Centre & UK Stem Cell Bank in South Mimms, Hertfordshire

The building has a large number of clean room laboratories and one of the requirements was to provide a well-insulated and weatherproof envelope capable of keeping out all external contaminants and preventing any internal biological agents from escaping.

One of the most challenging parts of the project was the curved section of the roof area. A full-scale mock-up was built to test the design, which uses straight and curved extruded aluminium T-section supports in a series of continuous ribs to create the shape.

The T-section supports are mounted on angle brackets attached to Kalzip aluminium seam clips that are fastened to the standing seam without penetrating the Kalzip. A continuous hidden gutter is installed just above top window level and 6m lengths of white chestnut are fixed to the T-sections to form the rainscreen.