We’d like to get as many materials locally as possible. Our roof will be turf actually cut from the plot. We will be using field stone - mostly glacial erratic boulders as revetting stone and a derelict dry stane dyke from 50m away as random walling stone. Aggregates will be from local quarries as far as is possible. The external larch cladding will be from the local sawmill and much constructional timber from the same source. Our SIPs frame will be made up at Milngavie near Glasgow - about 100 miles away. All hardwoods for kitchens, stairs and as much internal joinery as possible will be from Scottish sources. Not all our materials are able to be sourced in this way. The slate flooring and windows, will be imported and some bulky materials such as breeze blocks, cement and building sand will come from conventional builders merchants.

The biggest problem we face is site access, as the track to the site is pretty rough and very mucky in places. All materials will have to be transported in by tractor and trailer and the potholes on the track and drainage improved before we start. Our services have to be brought in underground - 550m for telephone, 250m for water and 200m for electricity.

SIPS are Structural Insulated Panels. They are a sandwich of polyurethane foam between two sheets of Oriented Strand Board. They are joined with wooden splines. As these create thermal bridges we will put in 50mm of additional insulation laid across the panels to eliminate cold bridging. SIPs no longer use CFCs or other gases as blowing agents. As they are structural they do not need additional frames internally. The roof will be self supporting as it is a conical shape with a structural band to stop it splaying out. This is pretty much the same engineering as a yurt.

Solar Wall

Originally we planned for a Trombe wall next to the south facing sunspace window but have changed our minds and will now have the solar wall in red Locharbriggs sandstone to the north of the sunspace  backed with a single course of dense blockwork. We will be able to ventilate the main roundhouse from the sunspace and circulate solar gains to the main open plan living space.