We are dealing with inspectors requiring some unreasonable things. Looking for input. The house is slab on grade with a 4' deep frost wall and wood framing above. We wanted to do a taper top, to the outside to get bearing under the wood framing to within 1/2" of the outside face of the ICF. So that the wood sheathing is flush with the ICF. The inspectors say we must have a constant R-10 on the outside of the foundation, therefore no taper top. They suggested having the EPS stick out 2.5" and install flashing on it. Instead the owner will fur out the upper wood framed walls. Next they required the installation manual for the ICFs be on-site. Now the inspector says the ICF frost wall must be covered with poly inside and out, to protect against deterioration.

I don’t know if this will help or be anything that you don’t already know... I am not aware of any code requirement specifying a continuous R-value. The code only requires meeting some minimum R-value...and you are certainly allowed to exceed code. Sometimes new inexperienced inspectors misinterpret code requirements or create code requirements that don’t actually exist but somehow seem appropriate to them in the moment. So it's always good to politely ask where exactly is that “code requirement” specified in the code? Often times an engineering stamp on the drawing will suffice in avoiding these sort of discussions. It’s always best long-term to do everything that you can to successfully work with and develop a trusting relationship with your inspectors...like exceeding code in some areas and making them aware of this and pointing out things that maybe they missed that you will better address.

I agree with Sailawayrb. We had some building inspectors refuse our mono pour, so we now have a boiler plate stamped addendum for the foundation plans. Perhaps this can be done with your situation. An engineers stamp trumps their ideas.

I should also add that it really helps to develop and maintain a positive attitude when working with inspectors or regulators. If you tend to think of them as adversaries or as a hindrance, that will only just continue to fester and lead to relationship issues. Like professional engineers, building inspectors have a strong obligation to uphold the public welfare and will lose their livelihood if they ever fail in that mission. So I think it helps to foster a positive attitude that they are here to help you from getting into a worse situation that is best avoided. Yes, I know at times this can be easier said than done when an inspector may appear as being over zealous and you are working to a tight schedule, but if you get a reputation of being a hothead and endlessly fighting with inspectors or regulators, this will not serve you well and will only lead to more misery.

If you are doing a 2x6 wall above the icf with the 2.5 inches of foam. You will still have 3 inch's of wood bearing on the wall. You can use the top plate to completely cover the top of the icf and help distribute the load.

Top plate should be pressure treated.

I vaguely remember that 1.5 inches is a code requirement for bearing. But I would search and double check that.

Also what is the slab sitting on? How are you covering the icf wall on the inside?

Good luck.....I went overboard with the drawings on my last build and it lead into all kinds of questions issues like you have. Sometimes I thing the paper sketch drawing philosophy works out better....

I thought we dealt with all this crap 20 years ago and it was done and over with

Depending on which ICF block you are working with, the manufacture hopefully has a competent tech support staff that can write a letter/make a call, etc, as to what you are proposing or have already done meets or exceeds the code requirement

Most inspectors are reasonable and understand that ICF is superior in more ways then one, and even though you do technically only have 1/2 at the top of the taper top on the exterior which is roughly R2.5, you have R10 behind it on the inside and R10 below it where the taper top ends, so averaging the wall you are much better then code requirements. Unfortunately common sense doesn't always prevail

I'd like to see where the requirement is for using poly to protect the wall, perhaps get the installation manual with all the manufacturers details on site, hand it to him and say...show me - and I could be out of line, it maybe a local amendment but not one I am familiar with