Lesson #1 - Why you won't find Polyurethane ICFs on the job site. Answer -

1. The foaming process creates a "skin" that prevents Concrete from bonding to the foam.

Why does the structural concrete need to bond to the foam in an ICF assembled wall?

Then why do EPS foam SIPs use polyurethane adhesive to bond to the skins?

Hey My WHY? was first.

Okay your why first... Because EPS is cheaper than polyurethane.

Yes I agree, also EPS is better at insulating, so Cheaper and Better.

ergodesk,

can you give facts as to "EPS is better at insulating". I am trying to figure all this stuff out and a factual answer with a source would really help!

Thanks

richm

Sure, http://www.epsmolders.org/

Environmentalists complain that EPS will not break down in land fills, but you never hear that about Polyurethane foam. Why?

ergodesk,

Just read the info at EPS Molders Assoc. I could not find where it said that EPS is better at insulating. They sure did write alot about the "aged" (or longer - 10 to 15 yrs) R values of polyurethane and iso. Tests have shown it to go down to 5.6/" whereas EPS lost no R value. That is very good to know.

It was also interesting to see their calculations for equal R values per x inches of material at prices that I have no idea as to the accuracy of.

Does anyone know the current price of 1 lb. density EPS, 1.2 lb EPS and polyurethane (NOT iso!!!) per board foot?

I would like to see some data collected since those tests were done in 1992. Do you know of anything in the works? There must be something - that was 17 years ago!

Also, please tell me if this should be a new thread:

Does anyone have experience with the relatively new EPS from BASF - Neopor. I have researched all I can find and it looks to be the next generation of EPS. Higher K factors, perhaps stronger, no info as to price. Is there a manufacturing plant in the US? All info I have found refers to it being from Germany.

Thanks for all the info all you contributors give!
richm

I would suggest that you contact many of the builders using the NEW BASF EPS Foams.

Arkie6;

you hit it on the head, it does not need to bond at all as it is not part of the structural component.
It is a thermal element of the wall