There may be no better way to build than with an ICF. You may as well build with your ICF more efficiently. Monopouring your footings and walls may be a viable option. http://fab-form.com/fastfootMp/naikoonCLM.php

My only problem with SCIP is the amount of conduction loss since the mesh connects the inside with the outside. If you want to upgrade the insulation values of an icf wall, you should consider a knock down form. It's easy to increase the thickness of the foam without the extra step and cost of using a standard block and adding inserts. I just priced out a job for a customer with 8" of foam and the cost blew away a standard block with inserts.

@Smartwall, remember, Polycrete inserts are 8 feet long, not 8 inches. http://polycreteusa.blogspot.com/2013/11/fix-it-anyway.html

Conduction from the footing into the center of the ICF wall is thermal bridging. Of course it helps that it's underground and blocked by 1/2 of the foam. I believe that the thermal mass advantage of SCIP over ICF outweighs the thermal bridging from SCIP wires (or you can make the SCIP foam a little thicker, so it's just a cost issue).

I've been looking and pricing. Around here you can pay a crew to form and pour a standard concrete wall, and add R40 of eps for less than the cost of DIY ICF at R20 somthing, or stick build to passivhaus levels for about the same $$

R40 of EPS (~10" thickness) will cost ~$3.00/sq ft for materials alone. 8" of poured concrete wall will cost $2.50/sq ft for the concrete alone at $100/sq yd concrete cost. That is $5.50/sq ft for only the EPS and concrete. That is not including any rebar or any waterproofing. In my experience on my project, you will need to figure in labor costs at least equal to the material cost if you are going to get someone else to do the installation, and in some cases at least double the material cost. I would estimate you are looking at a minimum of $11/sq ft of wall area for poured concrete walls with R40 insulation. My DIY cost for my ~R22 ICF walls was ~$6/sq ft for everything.

I know they make inserts and thicker exterior ICF forms but they are generally more pricier than off the shelf EPS sheets..... Most all DIY even contractors finishing the walls with a EIFS system, would have more interest in cheaper off the shelf EPS sheets to attach to a basic R22 ICF system.

If your cladding is to be EIFS what are some of the methods used to attach additional insulation to the exterior of an above ground ICF wall?

Posted By krom on 14 Sep 2014 12:34 PM
I've been looking and pricing. Around here you can pay a crew to form and pour a standard concrete wall, and add R40 of eps for less than the cost of DIY ICF at R20 somthing, or stick build to passivhaus levels for about the same $$

You could also use 8" cinder block which in most cases would be more than adequate for residential construction. Couple of issue I see with cinder block walls is that you still must fur or frame up the interior walls with stick framing and apply a liquid membrane on the exterior of the block to minimize moister wick. If you build a quality block exterior walls the labor and cost of forming headers and bond beams I'm thinking it would put the cost very close to 6" ICF wall and would be a better choice to build with ICF.  Would love to hear some more input and opinions on using cinder block with EIFS system DIY cost and methods.

I called a large building supplier in the southeast to get an quote for EPS foam .... Price was $25 per 100 S.F. for 1.5" EPS that works out to be $0.25 cents a S.F. for 1.5" EPS. I asked for the density of the foam but did not know so I cant state what the density was.

If your using EPS on a poured wall or block you would want thicker sheets, but 1.5" EPS at $0.25 S.F. will give you a good idea of just how cheap it can be bought for.

Pricing for a simple 28x40x8 rectangle

I've been quoted $31 for a 4x8x5" sheet of eps, delivered to site. ( $50 for 8" and $93 for 15")

For the basement I am pricing it would be $2100 to go R40 with eps, the Nudura quote I received was for $5100 (it included brace rental).

materials cost for an 8" wall is the same no matter what form you pour it in. (rebar, waterproof, etc)

That leaves a huge chunk of change to pay for labor.

What state are you located in krom?

Posted By krom on 14 Sep 2014 12:34 PM
I've been looking and pricing. Around here you can pay a crew to form and pour a standard concrete wall, and add R40 of eps for less than the cost of DIY ICF at R20 somthing, or stick build to passivhaus levels for about the same $$

I find that hard to believe but maybe your area is very unique.

Also make sure you are comparing apples to apples. ICF/Nudura uses Type II EPS not the cheap Type I stuff you find at the big box stores.

I'm in upstate NY

foam quote is for "EPS 15 Geofoam"  and comes right from the company making it, not from a store.

Posted By Lbear on 14 Sep 2014 09:06 PM

Posted By krom on 14 Sep 2014 12:34 PM
I've been looking and pricing. Around here you can pay a crew to form and pour a standard concrete wall, and add R40 of eps for less than the cost of DIY ICF at R20 somthing, or stick build to passivhaus levels for about the same $$

I find that hard to believe but maybe your area is very unique.

Also make sure you are comparing apples to apples. ICF/Nudura uses Type II EPS not the cheap Type I stuff you find at the big box stores.

I find it hard to believe that you continue to talk price about everything but your own quotes.  when are you going to give us a price on your Intus windows?

Details of the Product/Quote/Price is the most important thing anyone can share, and it should be shared, not hidden from view....

Those quotes run about 5 cents/R-ft for the material, which is significantly lower than when EPS is purchased through distributors. Typical installed costs for EPS run about 10 cents/R-ft, but you'll probably be able to beat that.

I assume the "15" in "EPS 15 Geofoam" indicates 1.5lbs nominal density/1.35lb min which would be Type-II)? That would also correspond to 15psi compressive rating too.

Dana, I assumed that too.

I did some more checking, and the quote is for type I 0.90 lb/ft3 min density

Any reason not to use it for the outside of a foundation, under a slab, or for persist construction? (I originally thought that persist would be too expensive, and have been looking at the Alaskan wall, but with this price for foam, and the reduced amount of labor, easier detailing of the air barrier it seems like a no brainer)

Sorry for the hyjack, but opinions are welcome

Posted By krom on 17 Sep 2014 09:04 PM
Dana, I assumed that too.

I did some more checking, and the quote is for type I 0.90 lb/ft3 min density

Any reason not to use it for the outside of a foundation, under a slab, or for persist construction? (I originally thought that persist would be too expensive, and have been looking at the Alaskan wall, but with this price for foam, and the reduced amount of labor, easier detailing of the air barrier it seems like a no brainer)

Sorry for the hyjack, but opinions are welcome

Type 1 should not be used below grade, whether below a slab or having soil pushing upon it in a foundation wall application. The main reason is that Type 1 is a lot weaker than Type 2 and this can cause issues where the foam gets crushed/compressed and can experience failure.

It's just not good practice to have Type 1 below grade. Type 2 or better is always recommended for below grade applications. Major ICF distributors like Nudura always uses Type 2 EPS, whether above or below grade.

On the other hand, EPS 15 Geo foam is specifically sold to be used below grade.

Posted By jonr on 17 Sep 2014 11:22 PM
On the other hand, EPS 15 Geo foam is specifically sold to be used below grade.

What I was thinking...

esp since it is designed for, and used as fill for under roads along with tons of other things


Does anyone have experience using it above grade, in an application like PERSIST ?

Most folks use a higher density EPS than 1# for under slabs. Most often we see Type IX which is 2# density or 25psi.