Would something like this be waterproof and vapourproof?
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http://www.homedepot.ca/product/leak-seal-black/996101
I want to put it on some wood that would have dirt up against the outside but be exposed to air on the inside.
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Replies
Alan,
First of all, it's almost always a bad idea to bury wooden components of a building. Dirt plus wood don't mix well. In general, I advise builders that below-grade components should be made of concrete or masonry.
The only exception is the so-called "Permanent Wood Foundation" system -- a type of foundation using pressure-treated studs and pressure-treated plywood. This system can work, as long as all of the essential elements are present: (a) All wooden components have been pressure-treated to a stringent standard, (b) all fasteners are stainless steel, (c) a waterproofing membrane like Ice & Water Shield is applied to the exterior side of the pressure-treated plywood, (d) there is a perforated pipe leading to daylight installed at the base of the system, and (e) the excavation is backfilled with a free-draining material like crushed stone.
An aerosol can of Rustoleum Leak Seal will definitely not protect any buried wooden components of your building from rot. Don't do it.