Withstanding loads without diagonal bracing
Because of the large open spaces, this highly engineered hybrid structure needed to take loadings beyond the norm. Post and beam structures readily withstand dead loading, but they require bracing to resist imposed loading such as the force of the wind. However, the architect, Page/Park, were keen to avoid the use of diagonal bracing found in most post and beam buildings.
Initially, consultant engineers tried to use a conventional studded wall system, but this proved impractical because of the high forces. Carpenter Oak in collaboration with several specialist companies, developed a solution, unique in the UK, using pre-fabricated wall panels with a central vertical ply sheet with top and bottom flanges (essentially a very tall beam) with vertical ribs at regular intervals to provide rigidity.
Additional technical detail
A final diaphragm skin was applied on site. These panels were used intermittently down the length of the building and across it to provide buttressing.
Further bracing was achieved with the unique floor beams which comprised of two vertical panels with top and bottom flanges creating an I box section rather than the conventional I beam.
The frame comprises 160 cubic metres of timber weighing in at 80 tonnes. All the timber was sourced from Scotland and the borders. It took 3000 man hours to fabricate in our Scotland yard and 3300 to erect on site.
Read more about Loch Lomond National Park Headquarters in the Architects’ Journal