Now making a start on the Reciprocal roof frame. Given the drawings are now finalised, it’s worth showing off the elaborate detail…

One of the design briefs was to keep lines clean and simple, very much unlike similar designs where round poles are laid upon one another. After many design revisions, the following design has been settled upon…

Reciprocal.1.COtf

The overall span of the frame is 6.5m, with a 1m opening for the central ‘lantern’. The roof is pitched at 15° and will be mostly supporting soil for a ‘living’ green roof. This will be supported on a laminated ring beam of plywood, to be eventually hidden within the 400mm thick cob walls.  The central lantern will house eight windows, capped with a curved oak shingled roof.

As the following picture illustrates, the framing will have some highly complex jointing.

Reciprocal.2.COtf

Given this is the first frame we have constructed with this type of detail, we thought it would be prudent to make a ⅓rd scale maquette…

Reciprocal.Maquette

Of course, much easier to assemble due to timber dimensions (40mm x 60mm). The real rafters are 180mm x 125mm @ 3.7m long!