Exterior sealing for straw bale house
About a decade ago a friend built a straw bale house in New Buffalo, MI. Look up its weather to see what challenges it faces.
Moisture is the biggest challenge. He tried for over a year to find a company in the Midwest that would spray a form of concrete onto the exterior or even one that would supply the material so he could spray it himself. The nearest one he found was somewhere between 900 and 1000 miles away in the Southwest.
Any suggestions how to finish the exterior of this building? It’s been kept dry with a conventional shingled roof with good overhangs (as recommended in the story on straw bale construction) and foam insulation boards and Tyvek, but it isn’t a finished building yet.
Thanks for all leads.
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Replies
Lynn,
The exteriors of most straw-bale walls are plastered (stuccoed). Straw-bale experts advise that you shouldn't cover the straw bales with any rigid foam or spray foam insulation.
The plaster is either applied directly to the straw bales, or is applied to chicken wire attached to the straw bales.
For more information on plastering straw-bale walls, and for a list of online resources, see Straw-Bale Walls.