Hello All,
 Does anyone know of a source for Insulated Concrete Forms that are designed specifically for Frost Protected Foundations?
I am wondering if there are any that have a 16" outer wall and a 12" inside wall. That would leave room on the inner side of the form to pour my 4" slab and finish the concrete at the same grade as the outer wall of the form.
Any help is greatly appreciated.
Will

Just realized I probably should have put this in the ICF category...

ICFs are easy to modify. A handsaw, table saw, or circular saw will cut down a 16" panel in no time at all. We do it all the time, and its a lot cheaper than having some company make special panels for you.

If you use ICFs, I suspect you'd give up the ease-of-construction and cost advantages of FPSFs. In the normal approach, you set the forms with 2bys and stakes, dig the beams with a trencher, set the foam and call the ready mix company. (OK, there are more steps involved but they wouldn't be any different between foam forms and dirt forms.) The slab and the beams are the same height because they are done as a continuous pour. You want a direct thermal bridge between the two; FPSFs rely on heat from the home's interior to warm the soil under the foundation and prevent frost heaving.

ICFs need a level base, and the slab typically is a second pour. There may be some nifty ways to overcome these disadvantages, but with ICFs costing five times more than XPS per square foot, dunno why you'd bother.

you can check out legalett system

Adi

Thanks for the input guys. I have decided against the ICF's.

Some FPSFs work using only the earth's heat and don't need a heated building.