Air sealing bottom plate to foundation
Roger_S39| Posted inGeneral Questionson
Hi all,
If Siga Fentrim F 6″ flashing tape is used on the outside of the home to air seal/flash the base of the Zip sheathing to the foundation, are any of the following products/methods necessary/make any difference, and if so how?
i) The use of a sill sealer (either the pink foam or the black rubber type)?
ii) Sealing the interior base of the bottom plate with a caulk (eg: Dynaflex 230)?
iii) Can spray foam on the interior side of the sheathing where the 2×4 framing attaches to the Zip sheathing?
Thank you.
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Replies
Roger,
1)Sill sealer is used primarily to stop moisture from wicking up into the wall by capillary action from the concrete below. it's worth including even it the sill plates are pressure-treated.
2) Belt and suspenders.
3) Belt and suspenders for builders with OCD
Hi Roger.
As Malcolm said, sill sealer has another purpose and should be used regardless of your air sealing strategy, though the gaskets do a nice job of air sealing too. Because this is a vulnerable transition with dissimilar materials prone to movement, most high performance builders shooting for low blower door test results take redundant measures here. Many do everything that you mentioned.