Apr 7, 2005, 8:53 AM
Post #13 of 17
Strawbale has been very successfully used in the more arid regions of Mexico, and has been used successfully in some humid regions of the US.
Do not depend on your lime plaster to keep water off of your walls, however.
If it were me, I would build with ample overhangs, probably extending the overhangs sufficiently to form a wraparound porch around your house. I would use an earthen plaster on the exterior of the bales, and would cover that with a ventilated rainscreen.
I'd build two or three small, inexpensive structures, and use the porches to extend the living space, around them. The climate is very amenable to this, and especially if you are doing some or all of the work yourself, you should be able to build in this way very inexpensively.
Take a look here http://strawbale.archinet.com.au/ for some examples of this general philosophy of construction.
I would also probably start with a single small structure, if your situation allows for it. Something big enough to be useful, but small enough that if the humidity does appear to be a problem, a building failure will not be expensive. Embed some moisture probes into the walls of the structure, and monitor it periodically for a year. At the end of that year drill out some samples and see how everything is doing. If adequately protected from liquid water, and if an earthen plaster is used, I imagine it'll be fine, but this would be the best way to prove that without risking a lot of $$$.
Athen and Bill Steen (http://www.caneloproject.com) have a lot of experience building with straw in Mexico, but their work has all taken place in the arid northern areas. Still, their web site and their writings are a great source of information on the topic.