EPS for under slab Radiant floor question

[bschwein]

New to the site and have been reading hours of information around radiant heat floors. I'm in the process of starting a pole barn build and installing a radiant heat system. I have found a bunch of good information here and appreciate everyone's contributions to it. It's helped me get started down the right path I believe.

I was able to pick up some 4 1/4" reclaimed EPS that came off of a commercial roof. The company that deals with this reclaimed insulation board said it was pretty high density board and it seems like it to me but I have no way of knowing what grade or PSI rating it is. After reading countless hours on EPS vs XPS, it seems to me that high density EPS is more than acceptable to use under a concrete slab.

My question is there any way to figure out the PSI or grade of EPS that I have?

Thanks in advance!

 

[bschwein]

I found a sheet that had some information still left. Would this indicate Type II EPS?

 

[purediesel]

Not sure if it'll help at all, but everything I have read says you shouldn't use EPS because it'll hold water and thus will ruin your r value. Should always use XPS under concrete and 25psi would be best. I read an article saying that sometimes 25psi is overkill for residential and the the 15psi could do just fine. I went with the 25psi XPS because it was on sale and cheaper that the 15psi.

 

[bschwein]

Not sure if it'll help at all, but everything I have read says you shouldn't use EPS because it'll hold water and thus will ruin your r value. Should always use XPS under concrete and 25psi would be best. I read an article saying that sometimes 25psi is overkill for residential and the the 15psi could do just fine. I went with the 25psi XPS because it was on sale and cheaper that the 15psi.

Appreciate your feedback and welcome anyone's. From what i've read EPS will actually release the moisture faster than XPS.

I've spent some time reading about both now. I've added a couple of links i've found discussing EPS for radiant floors including some from this forum.

**I guess i need 5 post before I can post links**