ICF is insulated concrete foundation

ICF = Insulated Concrete Forms

I was the architect for a five story hotel. We had a very experienced sub-contractor with ICF construction.

someone else was asking about TIPS or total in a graded panel system. It was polystyrene inside to thin concrete slabs. Not sure if that is similar to this but maybe find that post.

Our house was built with ICFs, and the original intent was for it to be our final home. That may change.

First lesson learned was to verify the builder's ICF experience. It may not be possible to visit the houses or talk with the homeowners; if not, then I'd want to see a portfolio of photographs taken during construction and to research the subcontractor who will do this part of the build. I don't want to say we were intentionally misled, but our builder wasn't as well versed in several areas of construction as his marketing implied. The sub who did our ICFs has a good reputation, but then so did the builder.

Next lesson learned was to not have a custom home, of any type, built while you're living far enough way that you cannot be on site frequently. I'm not certain we would have realized the extent of the errors in the early stages of construction had we been here but it's possible. This is more critical with ICF construction than with typical stick framing.

Our builder failed to adequately communicate with and/or supervise the company doing the ICF work. As a result the house varies from the plans enough to create problems which were compounded by interior framing errors/changes, only some of which could be corrected.

Think about why you want ICF construction and what other less typical choices you may make. In our case, it was largely about durability and safety. We chose to do a Fortified roof system and install storm/impact rated windows and doors (not usually done in our area.) Despite the errors, I'm still glad we went the ICF route.

If you're choosing ICF strictly for energy efficiency then look hard at the costs, both upfront and projected monthly utilities. The payback might not be there. At least in our area, concrete is still quite pricey and often hard to get. Does your builder anticipate any difficulty getting concrete when you'll need it?

One little thing - our window sills are deeper than usual. We like the look and could easily have quite a few plants growing on them. Our grandchild uses the nursery window sill as a seat and loves it. I look for positives like that to offset my ongoing frustration with other things.

Be ready for an almost cash build. The added expense runs through the whole proect, since you really cannot change concrete. Mistakes really cost. The appraisal will not value all of that invisibly spent money.

Its a nice upgrade