Air krete permeance measurement
user-1042388
| Posted in Green Products and Materials on
I am an electrical engineer, and I am designing a house for myself. I am comparing materials for permeance. I saw this perm rating document for air krete:
http://www.airkrete.com/testResults_files/PermRating.pdf
Please show me the math to convert the result in this document to units of US perms.
See http://en.wikipedia.org/wiki/Perm_%28unit%29
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Replies
Woodland,
The test report you linked to is a test for "water permeability coefficient" -- a rarely performed test, I think, that I have frankly never heard of. It is NOT a test for water vapor permeance.
The last time I spoke with R. Keene Christopher, the CEO of Air Krete, he told me that he had never had Air Krete tested for vapor permeance. However, it seems clear that the product, being cementitious and somewhat crumbly, has a high vapor permeance.