by David Cameron
In October of 1994 we started to build our straw-bale house. A friend who had seen straw-bale in Quebec and had some photo-copied information from the builder, Louis Gagne, and test information from Canada Mortgage and Housing, offered to help us get started.
My partner, Nancy and I had spent much time selecting a site-easily the most important part of the building process. We decided to locate half way up a south-facing slope, totally sheltered from north winds and set 100 feet back from the prevailing west wind track. This gave us a microclimate that allows picnics in the front yard on mid-winter sunny days!
Next, Nancy, daughter Tzigany and I drew plan after plan, We came up with an interesting hexagonal two-story core with single-story wings off the south-east and south-west, which friend Stirling McCann then drafted into professional-quality blue-prints. We wanted 1600 square feet for $40,000 or less (about 1/3 of going rate!).
Because we wanted to experiment with insulations and floor systems, we chose to set the house on a 24″wide x 10″deep poured concrete footer.
We intended a two story straw-bale house with single story wings. The late start and approaching cold weather convinced us to switch to wood-frame for the second story. Luckily we had available a lot of used heavy timber for floor rim and joists.
Since building this house I have completed a two story house for clients and stick by my early decision to do straw-bale as single-story only. The weight and complication of two story building with straw & concrete greatly slows the work and jeopardizes the quality and strength of the finished house as well as the safety of the builders.
A useful thing I learned on the second house was that the walls can be parged directly onto the straw-bales without the need of chicken netting or stucco wire. Some wire is still needed around window & door openings. Don’t use floating window-bucks if it can be avoided. Also order the windows early enough that they can be put in before parging to get good seals and crisp lines. CAREFULLY cover the whole window unit with poly to keep cement off trims & glass.
We have enjoyed our straw-bale hybrid home very much. The aesthetics are hard to beat-visually solid, sound and fire-proof, wide window-sills for plants and cats or even a place to curl up in the sun with a good book in winter. The insulation R-factor of straw-bale may be less than some people think but certainly is superior to that found in conventional construction.
Friends have an even friendlier straw-bale house. They parged inside and out with clay instead of concrete. There is a sensuous organic feel to clay that is more pleasing than the hardness and fst setting of concrete. However, clay does demand very wide roof eaves to protect exterior walls from rain.
We experimented with flooring systems ranging from beach stones and concrete over sand with no insulation and a poly vapour barrier, to planks “floating on 2×4 sleepers laid on a 6″ insulating pad of straw and poly barriers, to concrete poured over 6” scrap recycled styrofoam. All solutions have their points-the stone floor keeps the house cool in summer, the concrete over styrofoam is warm but breaks dropped china with alarming efficiency, and the plank over straw is the warmest.
After building our house at EarthSea I wrote a small booklet complete with drawings of essential building details and equipment. Terse and to the point, it briefly looks at the system options, explains how to make many of the forms and outlines the building process step-by-step. It also gives tips for avoiding the mistakes I’ve made!
If you would like a copy of our straw-bale building booklet, please send $10 in your currency or a check for $12 payable to EarthSea to: