Back in 2015 Robert and Lydia Somerville, with Joel Hendry and many volunteers, built a barn at their home in Burnham Green (Fig 1). Robin from BPCG went along to help and learn timber-framing skills.
Meanwhile back in Herne Hill volunteers had made a cob-oven for community feasts. This was in need of a roof in the autumn of 2016. Robin, naturally, felt that this could be made using traditional joinery techniques! Others joined in and helped – Marco, Hafren, Paul, Rod and Maria. Instead of Elm and Oak we used recycled softwood.
Starting by cutting the corner joints for the main frame – teasel tenons and lapped dovetails (Fig 2) – braces were then cut and peg-holes made in the posts and beams using an auger (Fig 3). Everything was assembled and tested (Fig 4) before being partially assembled and pegged together (Fig 5).
Work then started on the rafters using open mortice and tenons and step-lapped rafter seats (Figs 6 and 7). The rafters were jointed to a separate frame that would sit on top of the lower one.
When these had been tested, we put everything together around the oven, fitting and pegging the lower frames (Fig 8) and attaching the whole structure to the oven frame. Notice how the posts are floating on stones to prevent damp feet (Fig 9)! The rafters were then screwed together and onto the upper frame before a ridge board was fixed and a metal roof added (Figs 10, 11, 12 and 13).