Straw bale
This is an excerpt from an article in Sanctuary magazine issue 7.
Straw has been used as a building material for centuries. It’s an agricultural waste product, so using straw as a building material saves it from being burnt, which would release carbon dioxide. It’s a safe and biodegradable material, low in embodied energy and in cost, and is surprisingly resistant to decay and vermin. Being comprised mostly of air, straw bale is an excellent insulator and low in thermal mass, though this can be changed by the thickness and composition of the render.
While the material costs of straw bale are low, labour costs are high. Brian Hodge of Anvill Straw Bale Building Consultants says, “While we advise owner-builders to allow $650 per square metre we have seen cases where owner builders have been able to reduce this cost to as low as $350 per square metre. To subcontract out the work we would expect it to cost around $1,000 per square metre, which is a bit higher than a brick veneer home.”
If you’d like to build with straw bale but you want to keep costs down, consider being judicious with its use – carefully chosen feature walls could give you the maximum impact of straw’s insulating and aesthetic qualities while keeping cost to a minimum.
