Sealing holes in Hardie soffit
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We are converting our vented roof to a vapor diffusion port ( southeast US coast zone 3) and we currently have Hardie soffits. Easy access from the inside. What is the best way to seal these up? Cut individual blocks of wood to insert between the rafters, place directly over the soffit holes and caulk? Use something like 3m’s 8067 and just tape over the holes? Some kind of patching compound with mesh tape (if anyone knows of something appropriate)?
Any guidance would be helpful. I often see “seal off the soffits” but don’t see how people are actually doing it.
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Hoping to bump this for visibility as I think it got lost in the mix
kakey12,
I would use pieces of foam board inserted between the rafters where they go over the exterior wall, and air-seal them with canned foam.
Thanks Malcolm. I realize maybe it was a silly question but I can really over think things (I know canned foam isn't perfect and I was second guessing that) - so I appreciate your advice.
Semi-related question: is regular flashing tape like 3m 8067 or zip stretch tape compatible with fiber cement panels? I have some extra and was going to use it for a project. Can't find any info on that which I'm sure is because no one normally tapes the outside of their siding...
kakey12,
I'm afraid I don't know. Hopefully someone who has used them will chime in.