This post describes the work of Ramboll Computational Design during the design and construction of the Ongreening Pavilion timber gridshell. The detailed design was a collaborative effort between Ongreening Ltd. and RCD.

The structural approach involved form-finding bending-active timber laths in Kangaroo, connected at intersections to form a doubly curved shell. The final lath positions follow geodesic lines, making them simple to fabricate and assemble. Each lath was CNC cut from 6.5mm thick Finnish birch plywood laths that could achieve high curvature while maintaining desired strength.

Due to the random nature of the final lath topology, the resulting structure was extremely stiff in spite of its low material weight, acting similarly to a continuous monocoque. The Shell model was built in Grasshopper and continually analysed in Karamba, with this feedback informing the seeding of the secondary geodesics elements to increase the performance of the shell and make it suitable for public use. The fully demountable shell was first erected at Ecobuild 2014 in London.