Bristol Green House 2007	Straw
• blog • plans • links • home To express an interest or book your place, email: build@bristol greenhouse.co.uk • Foundations • Tyre walls • Straw bale walls • I-beam roof • Living roof • Clay/Lime render • Insulation • Earthbags • Map
	Strawbale wall construction. Straw is perhaps the ultimate eco-building material with incredible insulation properties and great load-bearing capacity. It’s also like building with giant lego. Let’s play.
	Fluffing Each bale needs to be squared up at the ends in a process called dressing. For some reason on our build it became known as fluffing.
	Pegging Hazel pegs protrude vertically from the wall plate, two per bale, to a height of less than a single bale height. The first row of bales are pushed down onto these. On the fourth course longer pegs, about 3 bales height in length, are hammered through, two per bale. The same was done again through holes in the bottom of the roof plate. The hazel pegs came from Lower Woods, Chipping Sodbury, care of the Gloucester Wildlife Trust, at a cost of 40p each.
	Grooving In our build I added vertical oak beams with adjustable bases to be able to even out bale compression over the three walls (each a different number of bales high). First we sprayed around a guide block, then we cut out the straw using a powered aligator saw. It is possible to do the cutting with a hand saw as well. The adjustable bolts were made by local blacksmith Fred Brodnax. In a conventional straw bale build these oak beams wouldn't be necessary as straw has great load bearing qualities. In our build, with only three walls, and each of those of different bale heights, these adjustable bolts will prevent some bales comressing more than others - especially those nearest where the fourth wall is missing.
	Finished back wall seen from inside and out