I recently posted a new “straw bale minute” video clip in which I argue that bale walls don’t breathe the way they have long been described as breathing. There is a divided crowd on this one. My understanding of how bale walls work is that the plaster is too thick to allow moisture to move through it. That does not mean that moisture laden air does not still find its way in and out of the walls.
Numerous outlet boxes and other penetrations supply ample space for such sir infiltration to take place. The idea of pushing moisture laden air through the plaster seems, to me, to be a false thought per recent studies and a PhD thesis I have read. Still, others disagree. For example, check out a response I got to my video clip:
“Maybe bales up in your neck of the woods don’t breathe after plastering, but they sure do breathe down here in the Southwest! I can’t tell you the number of times I’ve seen ample evidence of that. Just one eg: a gray water system that went through a straw bale wall broke and released probably 100 gal into the straw. I ran a sleeve around the 2 inch pipe, fixing the leak—and then just waited.
Within 2 months, and with no other assistance than being exposed to sun and wind, all traces of the moisture was gone. I had occasion to open up the wall from the inside a bit later, and was able to confirm that the moisture had transpired THROUGH the cement stucco. By the way, I specialize in straw construction here in New Mexico, have built about 50 houses and over 300 privacy walls.”
Clearly, the jury is still out on this one. I would like to hear more about how the author of this comment could know that the moisture moved THROUGH the plaster as he indicates. If he is correct, I would love to investigate this further and see how the two findings might be able to exist together. I like to live my life under the assumption of “Both/And” rather than “Either/Or.”