Caulking for sill plate
JSPIV
| Posted in General Questions on
I was going to caulk the exterior joints of mud sill as an extra precaution (it just had standard foam sill sealer under it). Is a standard caulk made for these substrates (such as Contega HF) suitable for this? Or is it better to use a vapor open product such as Prosoco or tape?
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Replies
I don't think vapor perm is important for this application. You want something that will move. My experience is to use a low modulus sealant something such as an acoustic sealant or such. I wanted a VERY tight seal so I placed two beads, laid a foam gasket, and then two more beads on top. Of course, that's overkill.
goatmig,
Contega HF is often recommended here as a more benign version of Tremco acoustical sealant.
Under the plate we use lots of Tremco's accoustic sealant but for really bad foundations I like a bead of Contega HF on the outside.
Thanks all. Yeah this is an exterior application to the seam, as the mud sill has already been installed. Sounds like something like Contega is a good fit. I read so much about vapor permeability... I just think I started overthinking it..