Wow!

Jay23...you were able to search back to a thread (and a silly argument at that) that no one has discussed in 18 months and decided that now was time to pounce on it again? Though I must say gncc35 deserves mad props, after 18 months of no mention of this thread, gncc35 was able to go on the defense within 12 hours!

Okay, I'm done...can we let this thread go back into the vault for another 18 months?

Allow me to correct myself, gncc35 was able to go on the defense in under 24 hrs....my bad.

Please renangle MAKE IT GO AWAY!!

Jay's apparently newer than me and still excitable.

I will point out that there are waterproofing systems available that are sprayed on in much the same way that a conventional Poured Concrete Basement has a tar based waterproofing applied. Just be sure they are water based, and NOT solvent based (couple brands are E-pro, Watchdog, etc.)

If you are not a fan of the membrane, then don't use it, but some form of waterproofing (or "damp-proofing") must be done whether you are using poured concrete, CMU, or ICF.

Also, gncc35 compared a 12" thick CMU to a 6" thick ICF and said it was the same thickness - this is true until you add insulation to the CMU, then you are losing (sometimes valuable) floor space.

Lastly, if you assume material costs, wall strength, wall thickness, ability to properly waterproof the structure, etc. are all equal - ICF still has the edge over CMU (or poured for that matter) in labour savings, and building performance.

Just my two cents in what seems to be a very heated discussion.

Just to let everyone know, because of some issues we were having with our property, we have not started building yet.
It has been almost two years since I posted my question about ICF and since then my builder has totally switched his opinion and has decided that ICF is a far superior way to go.
We will be building an ICF home from basement to rafters!
Thank you to everyone who shared their expert knowledge and personal experiences.
Monia Butler

Glad to hear it - I have yet to hear a homeowner build an ICF home and then regret it (except those who built the basement only and wished they continued with ICF).

Good luck and happy building.

First, I'll say that in general, an ICF and formed wall are no different for a given thickness and reinforcing. That said, curing is very important to achieve this, and forms should be left in place 2 weeks to achieve this well. Also, removing forms carelessly can damage walls. You don't have to address either with ICF.
I will also inform that there IS a difference between ICF and CMU. Forgetting the insulation for a moment, it's difficult to compare the two. They are designed by different criteria. The two walls designed "equally" for "equal" loads, will result in a weaker CMU wall. If a consistent, high-strength CMU can be acquired, it can come pretty close, but the amount of steel will likely vary.
CMU is much more trade-dependent, and a less-than-skilled mason will produce an inferior wall.
Below grade, most all but commercial grade constructed CMU will have a signifivantly shorter life span than solid concrete. And it will be more porous.
Lastly, I'd never use a 6" wall below grade (full height). Even if the numbers work, it will need more reinforcing, and will simply not perform as well should something unexpected occur.

In Alaska I built many single family homes, some in the most god awful leaky soils you can imagine using, cmu, icf and poured. First, the covering on the side of the foundation wall is really just "Damp proofing", not water proofing unless your seal under and around such that the darn thing will float because water will seek its own level, gravity sees to that. The secret to a dry basement is properly installed footing drains such that the water level never exceeds the bottom of the footing or slab. Do that and any foundation system will work, even treated wood, but the drain must daylight below the footing. Sometimes it requires damp proofing along with a vertical membrane to take the water all the way down to the footing drain.