Saturday, 19 September 2015

Roundwood Roofing

Our roofing job on the strawbale roundhouse is progressing well, with all the roundwood rafters on the circular part of the structure finished, and work started on the hip-roofed wing. 

The central compression ring was supported by scaffolding and bales while we fitted the rafters

Rafters notched onto roofplate
Strawworks built the bale walls and fitted the OSB roofplate and soleplate. Our rafters are then notched onto a 3x2" ring on the roofplate and birds-mouthed onto the compression ring. 

The noggins and intermediate rafters are fitted with a butt joint with angled flats to give a secure fit. This kind of roofing would be relatively simple with sawn timber, but marking up and cutting becomes much more difficult when working with natural poles. Roundwood timber framing is an evolving building style and working out scribing techniques for different joints is an exciting challenge.

These roundwood rafters will have laths laid over the top, which will then be plastered, leaving the poles visible. There will then be woollen insulation, topped by sawn rafters which will overhang the strawbale walls and then capped with a living roof.
The scaffolding support for the compression ring has now been removed - a big moment. The high number of rafters helps spread the load on such a shallow pitched roof.