Cushion Roof System for a Hospital Atrium, London

Over the past 15 years the performance of clear foils has been greatly improved. Of all those developed so far, Ethylene Tetrafluroethylene is the most significant structurally, as it offers excellent tear resistance, has very high translucency, and weathers well. Foils have translucent properties sufficient for a wide range of activities to take place beneath them, such as sport and horticulture. Used as double or triple skin cushions, they can provide significantly better thermal insulation than double glazing at only a fraction of the total weight. Clearly such considerations are paramount for wide-span roofs. At Chelsea and Westminster Hospital, London, such a cladding system was developed and incorporated into a sub-frame of purpose-made aluminium arches to provide an extremely cost-efficient solution to the problem of enclosing a deep central atrium.