Zip R and foundation overlap
nynick
| Posted in General Questions on
Quick question:
Zone 5, coastal CT.
We’ll be using Zip R 9 over the existing sheathing on our old house. This will then protrude 2 inches or so from the old foundation. What is the go to method these days for sealing the bottom of the Zip R and then that to the foundation?
There seem to be several methods on the web but no consensus.
Thanks
Nick
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Replies
Nobody?
Check this video at about 5 minutes in- https://youtu.be/IFdxRNsdcZ0?t=277
Also check out the Huber details- https://www.huberwood.com/technical-library/foundation-flashing-with-zip-system-r-sheathing
I'm not an expert so I give no suggestion over which of these techniques you should use. There are few details around which a consensus has been formed.
Thanks. That guy in MA has a good, clean solution.
Mostly good solution.
Foundation to wall is a large potential air leak in most construction, you want something a bit more than a bead of caulk to air seal. Before installing the wood strip on the bottom, instead of zip tape, run a piece of tape rated for adhesion to concrete down from the ZIP cross the foam to the concrete. Nail up the wood strip over this. Nice and solid air seal and less work.
Another option is to inset your framing so the sheathing is flush with the concrete. No overhang to deal with (except for foundation out of square) and the foam is protected without extra lumber pieces. From there it is standard ZIP install (ie stop 1/2" from the concrete and install backer rod into this gap). You would still need fancy tape or liquid flash for ZIP to concrete connection.