Can I use Platon as a cedar breather behind cedar wall shingles?
windfarmer
| Posted in GBA Pro Help on
I’m in zone 5A — SE Iowa — sheathing is OSB — Platon is a foundation moisture prevention product by CertainTeed — http://www.certainteed.com/products/foundations/waterproofing/311508 thanks, John
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Redstone,
My first reaction was "No -- it's vapor-impermeable, so you shouldn't use it."
Then I realized that the fact that it is dimpled may allow it to be installed in such a way as to permit airflow on both sides -- between the shingles and the Platon, and between the Platon and the sheathing. If it were truly ventilated, with air inlets on the bottom and outlets on the top, it might work -- but that's risky, because you are using a product for a purpose for which it isn't intended.
The same idea exists in a product designed for above-grade walls. The product is called Delta-Dry, and it is the only vapor-impermeable WRB that I know of. Read more about it here: All About Water-Resistive Barriers.