Find out, if possible, the maker of the foam forms. Then get their builder information package. Compare the building to that information. The fact that it is unfinished makes the comparison easier. Verify as much as possible that the correct amount and placement of rebar reinforcement was done.

Also do a image scan of the walls to make sure there are no voids in them.

Thanks very much for the replies...I had wondered about the points brought up by each of you, the amount/presence of rebar, and the possibility of voids.

How can I have an image scan done of the walls? Also, could it pinpoint the presence of rebar, as well as detect voids?

A local structural engineer should be able to do an image scan or find someone who does.

I'd see if the county code enforcement has the structural engineered plans on file. For ICF, most counties would require sealed plans. Otherwise, ditto on bus_driver's suggestions.

"For ICF, most counties would require sealed plans." This depends on where you would be building; there are probably more places that DON'T require them. We built an ICF house in a well-populated area where they didn't even require an architect's seal for anything--unless we were over 3500 s.f.

How much of the house is ICF? Just the basement? 1st floor? 2nd floor?

Check ALL walls for plumb and square. Otherwise, a framer/carpenter might charge more (possible window issues especially), and your final drywall job could look pretty bad. We talked to a couple of drywall subs who wouldn't even look at our job to bid it because they'd heard of bad ICF walls from somewhere.

Also, be sure you have an electrician who is willing to use a hot knife to cut channels for wiring and rig up backing for some switches under some conditions.

Anne

Make sure the plumbing is where you want it. Is there an outlet vent in the side wall for your range hood? Were other ingress/egress points planned for (cable, telco, electrical service, gas, etc.)? Otherwise you will have to drill.

Perimeter walls do not need to be hot-knived to run electrical. Buy a cheap electrical chain saw ($75-100) and drill a hole in the tip-end of it, 2 inches from the outer-edge of the cutting chain. Secure a 1-2 inch bolt through it (to stop it going any deeper) and then the electricians can rip away all the 2 inch deep channels they need very quickly. That's if your EPS is the typical 2.5 inches.

You can't drill holes through studs, or hot knife, that fast!

dallasbill, I just checked with DH who tried it both ways, and he said the chain saw as you described it worked best for the wires, but the hot knife was easier for him when doing the boxes.

DH also said to be sure your HVAC guys run a Manual J before determining what size furnace/AC you need, or it will be oversized. Almost all of the HVAC guys we talked to based the size of the unit on square footage, even after DH explained how tight the house would be. He said if they won't do a Manual J, use someone else who will.

He also said to be sure that the drywallers don't glue the drywall to the ICF foam. If they do, and if you ever need to remove the drywall (leaky roof?), the foam will be pulled off in chunks when you pull the drywall off.

Good point about the holes needed through the ICF walls. We had professionals do most of ours, since the largest were 6". We were the GCs and weren't sure exactly where they all were going to be, so we couldn't preset them before the concrete was poured. It was MUCH cheaper to have them come out just once to drill, since they charged per visit and per hole.

We had:

--4 hose bibs
--2 make up air (1 for woodstove, 1 for HRV)
--exhaust air for HRV
--hood duct
--dryer vent
--2 geothermal pipes (preset before pour)
--well pipe (drilled by installer)
--gas line
--2 electrical lines (due to geothermal)
--central vac exhaust
--central vac to garage
--septic/sewer pipe
--sump pump pipe
--gas pipe for patio grill
--telephone/cable

Anne

find out who built and poured the walls. icfs are not a dyi project. if an icf pro poured it i wouldnt worry about a scan.

Actually many people do ICFs as a DIY project, and not all pros do a good job.

DH and one other guy (experienced--had done 6 ICF houses) built most of our walls, although they had several people helping the days the concrete was poured. Ours turned out very straight except for a slight bow in one wall in the MBR. The concrete guys had also done ICF pours before. I walked around on the scaffolding behind the guys aiming the concrete, and I don't see how there could be any voids in our walls.

However, there are 80 or so companies making ICF forms, with maybe up to a dozen different systems being sold in any one state. Try to find out the name of your system--it should be somewhere on the foam forms. Then find out what the inside of the form looks like, and how much rebar was required. We looked at one system that was sort of a post and beam setup that I didn't want to use since I was concerned about the possibility of voids. (I also wanted solid concrete walls.)

The guy who helped us now sells the system he used to install, and he and DH keep in touch. The last time he was over, he told us of a job he lost to the most popular ICF system used around here, since the other salesman sold the materials to the guy for less. After the house was built, the owner contacted our guy and told him he should have used him. He said that his walls weren't straight, and that as soon as the subs saw them, they didn't want to work on his house.

Anne

Thanks, everyone, for your thoughtful, insightful replies. I'm sorry that I took so long to get back to this thread.

Actually, I visited the house again, and gained a bit more info. The ICF blocks used are Amvic, which, if I understand correctly, are a pretty good product.

I found out that the county building inspector heard somewhere (possibly from a concrete truck driver) that, during the construction of the basement walls, a "blowout" of the ICF blocks in one of the walls occurred. While studying up on ICF construction, I have read about blowouts, but wondered if any of you with ICF experience ever had to deal with one. Does the block break, allowing concrete to escape? Also, I assume that, once the blowout is corrected, it should have no lasting ill effects on the job. Is that true?

I inspected the wall where the blowout was supposed to have occurred, and see no evidence of anything out of the ordinary, at least from inside the basement. Do blowouts normally happen more on the outside of ICF walls?

Again, thanks for your patience in reading my posts, and for your replies.

I'm looking for a Insulated Concrete Form (ICF) contractor in Arizona. Does anyone have a recommendation??