The Construction of the Downland Gridshell

he first double layer timber gridshell in the UK has recently been constructed as part of a new building for the Weald and Downland Open Air Museum in West Sussex. Despite their many advantages, double layer timber gridshells are uncommon; the Downland Gridshell is only the fifth of its kind ever to be built. The reluctance to adopt this type of structure may stem from the difficulties associated with its construction, which entails the formation of the doubly-curved final shape from an initial flat mat of laths. The challenges presented by the formation process had to be overcome during the Downland Gridshell project. Issues that had to be addressed included the development of an appropriate formation technique and methods to monitor and assist the formation process. This paper describes the challenges presented in erecting the double layer gridshell and the solutions and techniques that led to the successful completion of the project.