Straw bale building

Energy-efficient homes are a hot topic right now, with everyone touting new technologies to build and insulate. But one of the fastest-growing methods is a 19th-century technique recently rediscovered – building walls out of straw bales.

Straw is plentiful; Ireland alone could probably produce enough straw to meet most of its building needs, without importing any more materials or clearing any more forests. It can form load-bearing walls or can simply insulate. It is easy to work with, and can be stacked and plastered by amateurs. Gathering and baling it does no damage to the environment, and the building waste can be made into mulch.

It is also one of the most perfect insulating materials around. Insulation is measured in “R-values,” and the higher the R-value, the less heat escapes the home. Most conventional homes are estimated to be R-12 to R-20; most bale homes, R-30 to R-50.

Isn’t straw flammable, you ask? Loose straw is, but bales are tightly compressed, and are no more flammable than wood. The National Research Council of Canada, for example, found that a straw bale wall withstood temperatures of up to 1,850 degrees for two hours.

Nor can the wolf blow the house down – the Building Research Center of the University of New South Wales, Australia found in 1998 that bale walls withstood winds up to 134 miles per hour – equivalent to a Category 3 hurricane.

To find out if bale building is for you, consult books like “Serious Straw Bale” by Paul Lacinski and Michel Bergeron, or “More Straw Bale Building” by Chris Magwood.