Timber-framed Cabin April 29, 2007
Posted by Graham in : Green Building , trackbackLast summer I started the construction of a small timber-framed cabin here at Derryduff. Aided and abetted by specialist Sustainable Builder Dave Simmonds, we put the frame up and had the tin roof on in about three weeks work. A couple of months ago we started again, Dave doing most of the building with me passing him screws and cups of tea when I’ve been around. The past couple of weeks we have been joined by Vasco who is visiting from Italy and has also been doing great work.
The project has been progressing well. The internal dimensions are 5meters long by 3.6m wide for the main living space which will be fully insulated; and another 4.5m by 3.6m for the adjoining workshop area which will not be insulated to such a high degree. This makes a total indoor area of about 33.2 square meters downstairs; and the same again upstairs in a “half loft” (1m65cms high at the ridge); so a total of 66square meters for an expected total cost of 25,000 euros. I feel this is good value for what is essentially a very high quality and low-impact “mini-house”. The final coat will depend on when I actually stop adding bit- eg i plan to build a “lean-to” extension the entire length of the back of the building, which will also house compost toilet and showers. It also doesn’t include my own labour.
Design features include: raised footings on concrete blocks with threaded bar bolting the fame to the blocks; 
split angled roof to provide 1m overhang for extra protection to the building; a steeper pitch to the front of the roof which is more suitable for solar panels; sufficient windows and a skylight for passive solar gain; and plenty of insulation: Warmcell (loose recycled paper product) insulation in the floor; 5inches of polystyrene in the roof; and loose, washed wool in the walls:
I bought a bale of washed wool (industrially washed in the UK- Im not actually sure where the wool itself came from) -230kgs for 230 euros (plus 72 euros delivery); I expect that to do the whole of the downstairs walls in the main cabin, and the thinner (3 inch) walls in the worklshop area, with some left over. This makes it one of the cheapest and most cost-effective materials used in the whole cabin, far cheaper that wool-insulation products, and easy to install if you first zig-zag string or cord of some kind across the studs using staples to hold it in and then fill in behind. The wool is a really nice material to work with (in constrats to the quite unpleasant polystyrene and foam!) and addsa really nice soft and , well, feminine feel to the inside of the building.
The walls will be covered in SasmoX sheeting, which will also add racking strength.
The exterior will be clad in larch boards cut from the Manch estate near Dunmanway.
Comments»
A very nice building Graham. You will be comfortable in that. Any chance of finding out your source of washed wool?
Looks great Graham - one thing though, would there not be cause for concern with the warmcell in the floor being adequately protected from moisture? It turns to porridge quite quickly if exposed to water, as the Stroud co-housing project discovered after a plumbing mishap….