I had a great 3-day visit to Wimbledon erecting and glazing this large accoya structure. Apart from the shelving, everything is made from accoya - which is guaranteed to last for 50 years without maintenance and covers against rot or any type of insect attack. It's also uv stable and won't warp or expand through the seasons - so the doors and windows will fit tight as the first day they were installed.
I use a metal acro prop to maintain a straight ridge line before adding lots of horizontal supports to the large (4x2") rafters.
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