# 2" radiant slab insulation



## PLUMB TIME (Feb 2, 2009)

Okay all you radiant guys, I need help, kinda.
I'm adding a garage addition in the northwoods and am going to install 2" tongue and groove styrofoam under the slab (on top of 6 mil. vapor barrier).

Is this stuff really $32.00 a sheet or does anyone have an on-line or other resource for it that may save me a few bucks?


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## RealLivePlumber (Jun 22, 2008)

Why do you need 2" in the field?

Its more important for the edge.


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## futz (Sep 17, 2009)

Around here they don't bother with tongue & groove. By the time you stomp across it for a day or two laying loops the tongues and grooves would be completely destroyed anyway. Just plain 3" white styrofoam over 6mil poly. They use styrofoam kant strips (triangle cut) around the perimeter to give that last 3"-4" at the slab edge some R value.

I don't know what it costs. The builders do it - it's code required.


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## Plumbdog (Jan 27, 2009)

I don't recall the name of the product, but on the last radiant slab that I did I used this styro that had built in nubbs to hold the pex, no zip ties no bending over you literally tap it in to the nubbs with the tip of your boot. The suff was the balls. i'll see if I can find the name.


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## breid1903 (Feb 8, 2009)

http://www.viega.com/xchg/en-com/hs.xsl/693.htm. breid.........:rockon:


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