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Community and Q&A

Paint Permeability for Clapboard

jsbb | Posted in General Questions on

I have a 150 year old house. I recently removed the aluminum siding and am restoring the original wood clapboard. I presume I should use a breathable / permeable paint when it comes time for painting. How permeable should it be?

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  1. Expert Member

    Most modern acrylic based exterior paints are very permeable, and durable.

    Benjamin Moore's "Regal" line is quoted at ~50 perm

    Sherwin Williams doesn't seem to share that info in their tech docs, but I'm sure it's up there too.

    There's not a lot of control in choosing a desired permeability - just go with a good paint, apply it well, and it'll perform as good as anything else you could have applied.

  2. jsbb | | #2

    I believe Sherwin Williams puts their Super paints at ~27 perms and their Emerald at ~29 perms. Is that sufficient?

  3. Expert Member

    Yes, that is sufficient.

    Anything over 10 perms is considered to be very vapor-open, and will allow drying when the conditions are right.

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