[GSBN] Failures due to moisture migration in bale walls
Jacob Deva Racusin
buildnatural at googlemail.com
Sun Jun 28 21:01:46 CDT 2015
We've been moisture testing bale walls in the cold climate of northern
US for over a decade, and have yet to see any damage primarily as a
result of a lack of interior vapor barrier and resultant vapor
migration. We have seen issues as a result of a cold-side vapor barrier
- in the form of pure cement stucco - but that's it. I'm happy to talk
more off-list if I can help supply particular materials or informational
sources. If it helps with documentation, we produced a report based on
commissioning of a series of buildings we built that discusses this and
related durability issues, which you can download off our website here:
Best of luck,
On 6/27/15 11:35 AM, Chris Magwood wrote:
> Hi all,
> I'm working on a "defense" of the vapour permeable nature of straw
> bale walls for a building code for an alternative solutions
> application here in Ontario.
> The building department is particularly concerned about the lack of a
> vapour barrier in the system (again!). I'm pulling out all the usual
> test documents and building science theories to help make our case.
> But I'm interested in knowing if any of you out there have actually
> encountered a bale wall that has failed due to moisture migration
> through the wall, especially during the winter. I've certainly seen
> some damage done by consistent exposure to rain, or leaky roofs, or
> other bulk-water intrusions, but I've never seen a moisture migration
> failure. If that has been the general experience of this list, with
> its wide variety of climates and building styles, then that would seem
> to me to make a good evidence-based defense for this.
> And if you have seen such a failure, I'd be interested in knowing
> about the suspected (or known) causes, the conditions that led to this
> failure, and whether or not the situation was able to be remedied.
> I don't need everybody on the list to respond... perhaps only those
> who've seen examples of this type of failure. If the list is silent on
> this, I'll take that to mean that this really hasn't shown itself to
> be a major issue, and will say so in my AS application.
> Thanks all!
Jacob Deva Racusin
New Frameworks Natural Design/Build
Author, The Natural Building Companion
Chelsea Green Press, 2012
jacob at newframeworks.com
More information about the Gsbn