Sustainable Works is an Alberta and British Columbia based sole proprietorship involved in education and implementation of basic ecological design principles. Our work has been as far a field as New South Wales, Australia, Maui, Hawaii, as well as throughout B.C., Alberta and the northwestern United States.
The resource issues surrounding affordable low impact housing are numerous and widely discussed. One simple proven technology is plastered straw bale construction. Its main advantages are low cost, energy efficiency with R-35 walls, the use of an annually renewable resource, healthy “breathing walls” without vapour barriers which can hold volatile organic compounds within a building, a two hour fire rating confirmed in two separate international tests, and resistance to earthquakes.
These issues and the engineered prescribed building code standards for plastered straw bale construction form the basic topics covered in our consultations, seminars and workshops.
Straw bale construction began at the turn of the 20th. century in the Sandhills region of Nebraska. Homesteaders lacked both trees and sods to build their homes so they used their recently invented balers to produce meadow hay bales to stack as wall material. The bales were laid like bricks, pinned together with wood stakes and the roof was built directly on the walls. The weight of the roof compressed the walls during a one to two month settling period. After the walls stabilized in height, the builders plastered the walls with adobe, lime plaster or traditional lime cement stucco. This is the traditional Nebraska or load bearing method of straw bale construction that flourished in this region until the 1940’s when it was replaced by stud frame building.
In the early 1980’s, builders in Quebec and New Mexico began to experiment with baled fibre construction. Research sponsored at this time by the Canadian Mortgage Housing Corporation determined plastered two string straw bale walls had an R-value of 35, nearly twice that of a conventional stud wall and fire tests gave the stucco plastered bales a two hour fire rating which is the equivalent to the requirement for commercial buildings.
Recent CMHC research in bale wall moisture and pre-compression of load bearing walls has attracted international attention. In 1995, Fibrehouse Ltd. in Ottawa received a grant to test their air bag method of compressing load bearing walls. The result is a stressed skin system which lab tests determined can resist seven times the Canadian hurricane requirement for wind loads and 2.7 times the vertical load requirements for two story homes in most parts of Canada. In 1996, Don Fugler, an engineer at the CMHC Research Branch, funded a study that lead to the design of two simple bale wall moisture sensors that researchers use to keep track of the seasonal variations of moisture in the “breathable” straw bale walls. The moisture sensor research and the Fibrehouse air bag pre-compression system are important parts of Sustainable Works activities to promote simple, safe, and affordable low impact housing.
Sustainable Works has been contracted by CMHC for two research studies, on bale wall moisture (Dec.1999) and thermal energy efficiency (April 2002).
We offer a full range of services for the owner builder beginning with design and building permit application consultations. The methods and materials recommendations are based on up to date Canadian and international research and testing for bale walls in our local bioregions. We lead wall raisings and stucco plaster work parties for those wanting to share the work and learning experience with family and friends. Contact Habib directly at: email@example.com 250-354-9711 or 780-438-0821.
Sexsmith, AB, straw bale church built in 1954