ICF Stem Wall Questions

[Milo]

Having a shop built with an insulated slab floor and the builders are about to dig for the footers. I drew it up using concrete block with 2" EPS foam up the stem walls and under the slab. The builder just mentioned he might just use ICF's because they do them themselves and finding block layers is always difficult. From what I've researched it seems reasonable, maybe even better. ICF's are available in a waterproof version also one that is resistant to termites, should I insist on those versions? One concern is the 6-8" exposed on the outside below the siding? Can't leave just the foam exposed need something over it to protect against UV, string trimmer, etc. Any suggestions to cover the outside ICF's from just below grade up to the siding?

 

[RNeumann]

I would not specify that the ICF be the waterproofing. I’d be more inclined to find a waterproofing method or contractor that you like and specify that. I don’t personally think the ICF would make a good waterproofing membrane but I haven’t researched it. I used a more homogeneous style.

 

[bigtiller]

I would suggest an ICF brick ledge. Then you could put on a brick veneer to cover the exposed styrofoam.
My builder didn't do that, he mixed up small batches of concrete-patch and actually smeared it on with a gloved hand. It's been there for 20 years with so-so success, just don't bump it with the lawnmower or it will crack and fall off.

 

[Milo]

I know concrete blocks below grade are parged with a bonding cement then some kind of tar/ sealer, ICF's require steps to accomplish this as well?

Brick ledge is a good suggestion then I can put bricks, fake stone, etc. myself.

 

[RNeumann]

I know concrete blocks below grade are parged with a bonding cement then some kind of tar/ sealer, ICF's require steps to accomplish this as well?

Brick ledge is a good suggestion then I can put bricks, fake stone, etc. myself.

The ICFs, I’m thinking, would also need a multi step process. I don’t see how you could get as good of a seal with just an ICF- no matter the factory applied sealer. I think some sort of homogeneous coating applied afterword is needed.

 

[Milo]

Sounds right RNeumann, I need to learn more about ICF walls.

 

[RNeumann]

The ICFs need a waterbased coating or a peel and stick that won’t destroy the foam.

 

[Milo]

Thanks, I'll be sure the builders incorporate one or the other. Now if it would ever stop raining so the ground can dry up....

 

[Stomper]

I am on a pressureized sewer system where I live and just finished building a small lift station. 6 feet of the building is below grade and I used the Amvick ICF's. One thing that I have learned about them is that they are GREAT and extremely easy to work with. They aren't cheap to buy but in the long run, they pay off. The reason I used them was the ease and speed of instalation and the insulating factor, 2" on the outside and 2" on the inside. As far as waterproofing goes, they do require it, at least the ones I used did. I used the "blueskin" peel and stick membrane by Henry with a liquid primer applied to the ICF's before the peel and stick. The membrane sticks good on it's own but with the primer applied you better make sure you stick the membrane where you want it because you don't get a second chance. The primer has to be a water based primer designed to be used with ICF's because a solvent based primer will destroy the foam. You will also want to put some sort of hard protectant over top of the membrane to protect it from cuts and abraisions, I used the Delta MS stuff and just screwed it to the nailing ribs in the forms.
Next time I have to build a insulated concrete wall, ICF's will be used. They are amazing. Hope this helps

 

[Milo]

Thanks Stomper it does help! I haven't had the opportunity to talk with the builders in detail just how they plan to keep water and moisture out but with this info at least I know what to talk about and ask for. At this point they're still chipping rock to get below the frost line.