In another thread about porch flashing, I said we’re doing an insulated concrete form foundation for our new home. Someone pointed out that Grace Ice & Water Barrier is a good waterproofer for ICF systems, which answers half my question.
The other half is – for those who’ve done such foundations, what do you all put over the IWB? I need some education here about materials and methods – We’re looking at some sort of brick product, but for my info, how do you go about attaching the stuff?
Do you just cast brick ties into the ICF & run them out through the foam insulation, then treat like an ordinary brick facing? I could handle that, but with my luck, there’s some other arcane thing that no one in my area can do. ; )
What if I wanted to use something like Nichiha or Synstone? Nichiha makes an autoclaved concrete product – Synstone is a polyurethane simulated-stone product, both of which come in panel form. Synstone can be PL400’ed on, while Nichiha’s product has to be nailed.
Thanks for any/all advice. This place has been a font of information up to now – I can’t imagine that’s gonna change. : )
Jason
Replies
The IWS goes below grade.
A full brick wythe will need a brick ledge cast in the ICF system - the ICF mfg can provide guidance based on what you are trying to do. Review their details book or call the rep.
If you are talking about a veneered or cultured stone/brick facing type solution, some say you can scratch the EPS (Expanded Poly Styrene), apply a scratch/parge coat and have at it. Others recommend tarpaper and metal lath attached with screws into the ICF ties with screws that have large plastic caps behind the heads. I think a FHB in the last year talked about the direct application method.
The plastic panels show promise for some applications, but they don't do the corners well (IMHO)
We are going with the T-mass system because of the issues you are facing (no pun intended). I am not finishing my basement right away, so the concrete interior does not need an immediate fire barrier as the foam would. We plan on doing cultured stone veneer on the exposed parts of the foundation, but not right away. I am less worried about leaving concrete exposed for a couple of seasons than I would be if it were bare EPS.
(T-mass is 2" of foam sandwiched in a poured wall - 4" conc, 2" foam, 4" conc - R-17 performance - not as high of an R value as SIPs, but still pretty good.)
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An online journal covering the preparation and construction of our new home.