Two New Books on Straw Bale Building

Build It With Bales: A Step-by-Step Guide to Straw-bale Construction

by S. O. MacDonald and Matts Myhrman, 1994. Out on Bale, 1037 E. Linden Street, Tucson, AZ 85719. Softcover, 80 pages, $22 postpaid.

The authors of this short, refreshing book present the basics of straw-bale building for an owner-builder audience. There is a fun irreverence that makes Build it With Bales a great read: from the photo of Myhrman in a pig disguise to MacDonald’s suggestion that you throw out the television.

The book provides a quick way to get up-to-speed on the nuts-and-bolts of straw-bale construction from two people who obviously know a lot about the topic (Myhrman publishes The Last Straw, a quarterly newsletter on the topic). Particularly good is a question-and-answer section at the beginning of the book that directly addresses the most common questions posed to straw-bale proponents. We were also very pleased to see an emphasis on reducing the environmental impact of buildings throughout the book. While the book provides a useful addition to a builder’s library on this construction system, building professionals may be disappointed by the limited depth of the book and the owner-builder slant.

The Straw Bale House: Designing and Building with a Resource-Efficient Material

by David Bainbridge, Athena Swentzell Steen and Bill Steen, forthcoming December 1994. Chelsea Green Publishing Company, White River Junction, VT 05001; 802/295-6300. Approx. 320 pages, $25.

Like such pioneering works as The Passive Solar Energy Book by Ed Mazria and The Timber Frame Home by Tedd Benson, The Straw Bale House will likely become the Bible of straw-bale building. The authors have done a superb job at providing enough basics to make the book understandable to homeowners, yet enough specifics to make it highly useful to professional designers and builders. On top of this, the book is fascinating to read, with lots of historical information on straw-bale building and many photographs of both old and new straw-bale buildings. The book includes more than 240 black-and-white photographs as well as 16 pages of full-color photos.

We were a little mystified by the order of several of the chapters (the foundation chapter follows the chapters on walls and windows/doors, for example), but clearly the key information is all here and readily accessible. In the chapter addressing common concerns of straw-bale building, there are some great anecdotes that will help builders and designers alleviate concern with this new (and still unusual) building system. In one example, a candle was left burning overnight in a wooden box that was set in an alcove in an unfinished bale wall (the stucco had not yet been applied). The candle burned down and caught the wooden box on fire. All that was left of the box in the morning was ashes; the straw bales charred but did not catch fire and were cleaned up and finished without problem. Humidity and moisture are called the least understood aspects of straw-bale construction and the area where future research is most needed.

Information on working with bales is excellent and will be highly useful to builders. In the chapter on bale walls, details are provided for both load-bearing and in-fill approaches. An essay is included in the book by a builder who analyzed costs and wood use for two nearly identical 900 ft² straw-bale houses he built: one with load-bearing bale walls, and the other with non-structural in-fill bale walls. He found, quite surprisingly, that the in-fill system, in which a simple structural frame supported the roof, was less expensive to build and actually used less wood! Because structural posts are typically held in place by the bales, much lighter wood frames can be used than are common with timber-frame houses, and the top plate can be much simpler and less wood-intensive.

Environmental advantages of straw-bale building are emphasized throughout the book. In terms of energy efficiency, three-string, 23-inch-wide bales laid flat are said to provide an R-value of 54.7; two-string, 18-inch-wide bales laid flat provide R-42.8. Regarding resource use, the point is made that if straw currently burned in the fields were used for building instead, some five million 2000 ft² houses could be built each year! The embodied energy of straw production is listed as 125,000 Btus/ton, but it is not specified if this figure includes only the energy expended after the grain is harvested—since most of the energy for straw production should logically be accounted to the primary grain product. Straw bale walls are said to be 30 times less energy intensive than wood-framed walls with equivalent fiberglass insulation.

In comparing these two books, both have value for the builder. Build It With Bales provides a very quick way to get a good idea of what straw bale construction is all about. The concise book is clear, direct, and informative. Builders wanting to go into greater depth and wanting to show potential clients what straw-bale buildings actually look like will want to buy The Straw Bale House. Taken together, these books significantly move the straw-bale building movement forward.