Fredy Brunner

Straw used in house construction

The walls of Jana and Fredy Brunner’s two-storey house, at half a metre in thickness, are made of straw bales.

When the walls were completed on the weekend, Jana and Fredy Brunner’s two-storey house looked like a traditional home with stucco walls, but the recessed windows suggested the thick walls were not conventional house construction.

The walls, at half a metre in thickness, are made of straw bales.

Habib John Gonzales of Sustainable Works was responsible for the straw bale walls at the house on Garnett Valley Road.

While the building material is not common in Canada, it has been used for other buildings in the region including a house in West Kelowna and a winery in Cawston.

Straw bale houses have been constructed in Canada since 1984, when the first was built in Quebec.

Because straw bale houses are not yet common and because the construction is not governed in present building codes, an engineer’s stamp of approval is needed for the work, Gozales said.

He added that the bales used are not the same as typical bales from farms. They have a prescribed density, moisture content and fibre length.

“They’re much tighter and more dense,” he said. “There are engineered standards for this.”

The completed walls, once treated, will meet two-hour fire resistance standards.

The walls also have a hurricane rating seven times the Canadian standard.

“The wind can blow. It’s okay,” Gonzales said.

Gonzales said straw bale construction has been used for some duplexes and triplexes in Alberta.

“We had an arson attempt on a building in Edmonton and it went nowhere,” Gonzales said.

Fredy Brunner said he and his wife did much research before choosing to use straw bale construction.

“Our main interest was its high insulation,” he said.

The walls have an insulation value of R35, nearly twice the minimum required value in British Columbia.

Further construction is continuing on the house, which is close to 200 square metres.

The Brunners hope to move into the house in November, while the last of the work is finished.