Best and cheapest way to connect Zip R9 to foundation
I’ll be using Zip R9 on my current build. This is an north/central Indiana climate zone 5 build and will be on a full 9′ basement. I’m wondering the best way to connect the Zip to the foundation would be for the money. If I use some sort of elastomeric caulk under my sill plate, then I can just caulk the zip at the bottom to rim joists? There’s also the zip liquid flashing or something similar or a tape like Siga Fentrim (are there other cheaper options?). If I do either of these options, then do I need to apply caulk under the sill plate? Just looking for the cheapest/easiest option, if that exists. My perimeter is about 350′, so Fentrim would cost about $550. If I don’t have to do caulk at the sill plate with that option, maybe that would be the simplest and cheapest? Any advice would be welcomed!
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There are a number of details in the ZIP installation manual. You can use liquid flash with backer rod. There are also other acrylic tapes that are compatible with ZIP and concrete (ie 3m8067).
If I liquid flash or tape, do I still need to sandwhich caulk over and under the sill sealer under the sill plate though? That would be redundancy, right? I'm fine with just a belt if that'll hold the pants up flawlessly.
We used an elastomeric caulk that stays soft when dry under our sill plate. Then I noticed that our concrete was not level and we had large gaps in places that you could see directly under the sill plate into the house. I then applied a liquid flash on the outside around the entire house. This was very time consuming and if I could do it again I would use a tape that can be used on concrete and wood.
Fentrim is amazing tape. It sticks well to concrete and conforms to irregular surfaces. I used it outside to seal the sheathing to the foundation and inside to seal the crawlspace encapsulation plastic to the foundation walls. I haven't seen any tape to replace it.
VI would like to make the case for zip liquid flash- there are many similar/competing STPE formula products (Henry air bloc LR , prosoco fast flash etc, indeed it’s a poorly kept secret zip just rebrands the Prosocco ,product and changes colorbut zip is competitive in terms of price and coverage and durability. So let’s price it out to cover that 350 linear feet of joint - figure four inch tape on a zip r9 (1.5” thick) will give you 2 inches in the concrete and 1/2 on the zip exterior green side . I think that’s adequate. Figure with shipping and taxes, etc $110 for an 85 foot roll, you’ve got to buy 4 rolls to get 350 feet, so $440 that route and probably an hour max to install . For liquid zip $35/2o oz sausage , prosocco fast flash $28, Henry lr $25; for prosoco figure every 20oz will allow you to cover about 18 sq feet, or 54 linear feet 4 inch wide, so 7-8 tubes, so ~$230….for same 12-15 mil thickness Huber site indicates you’ll,only get about ten Lineal feet 4 inches wide .so,let’s split the difference and figure the liquid flashes will cover 14 lineal feet per tube, so need 8-9 tubes . But the labor is obviously greater-still don’t have to worry about tape -pealing off in the future.