Crete Heat

[Friartuck]

The topic of insulating under the slab for radiant heating has been batted around this forum and this is just one more version. Has anyone used Crete Heat insulation panels? This is the 1 or 2 inch thick 25 psi polystyrene panels with plastic disks on top to ease the installation of the pex tubing between the disks. Any pricing info?? Foamular 250 at 2 inches thick is about $1.00 per sq ft, so how does Crete Heat compare? For someone who is not putting a dollar figure on his labor and planning to zip-tie pex to wire, is it worth it?

http://www.crete-heat.com

 

[Possum]

I don't remember exactly how much I was quoted, but if I recall correctly those were about double the cost of XPS when I was checking into them.

 

[falcon428]

It was about double the cost when I looked at it, i bought the Foamularf for about .60 cents a sq.ft. on sale. and the cheapest anyone wanted to sell the crete-heat was 1.48 a sq.ft. and that was a semi load price. I was also told I would do better with pex tied to rebar and pulling it up in concrete halfway. Crete-heat does look to be an easier install, but on 9300 sq. ft. I chose the other way out.

 

[GreenInsulation]

Re: Crete Heat Pricing

Crete-Heat the 2 inch will give you a more constant R value than other insulation which tends to "outgas". It has shiplapped joints providingfor a continuous thermal insulation, 10 mil polystyrene film vapor and radon barrier, has the 3" on center fasteners that allow for quick tubing installation . It is a simple install product that holds the tubing, insulates and provides vapor barrier all in one product. The install time is cut up to 2/3's!! When you are doing radiant, who wants second best? See a video at www.crete-heatinsulatedfloorpanelsystem.com

 

[jklingel]

"Crete-Heat the 2 inch will give you a more constant R value than other insulation which tends to outgas". I'd like to see some independent research on that. Frankly, I don't think the off-gassing in XPS amounts to much. Polyurethane foam off-gases, though. Looking at the specs on CreteHeat, the R-value is the same as XPS (minus the alleged off-gassing reduction, which I've not read about being much.) The perm rating is .51, whereas I think 2" of XPS is about 1 (more permeable), but 6 mil visqueen has a perm rating of 0.06. There are better, tougher vapor barriers/retarders, too, (Tu-Tuff, for one) that ought to go down regardless of what "insulation" product you use; all foam sheets have edges that leak, esp because you can not install them perfectly lined up, esp after the job is completed; too much traffic. I'd be careful w/ the psi rating, too; my engineer called for 40 psi XPS under my slab, FWIW. CHeat looks fast, but spendy, and I am not convinced you are getting a great deal out of it. That's my 2 cents. john

 

[Daniel Dudley]

I have always run rebar in my slabs, so the radiant gets wired to the rebar. Possible overkill, but I like the idea of the rebar in there.

 

[Friartuck]

Since I started this thread I learned that the high cost of crete, about 3-4 times the cost of regular Foamular 250, is not a value for the regular homeowner. I guess the only savings is in labor for large projects like a 10,000 sq ft aviation hangar. I can bend over and zip tie 1000 feet of pex and use the $1,800 in savings for the tankless heater and manifolds (and have $$ leftover for ribs and beer for the concrete crew).

 

[GreenInsulation]

http://www.reavesbuildings.com/images/eps1018-30-year-test.pdf

If anyone cares to read this.


Crete-Heat can also be made to be 40 PSI for heavier jobs.

 

[tdkkart]

http://www.reavesbuildings.com/images/eps1018-30-year-test.pdf

If anyone cares to read this.

Blah, Blah, Blah, yada-yada.

A test of insulation on a roof has nothing to do with the same or other products when used underground.

 

[jklingel]

"I have always run rebar in my slabs, so the radiant gets wired to the rebar. Possible overkill, but I like the idea of the rebar in there." It is pretty cheap insurance, IMO. #4, 12" OC should do most slabs. If you run heavy equipment, see an engineer, but I'd guess that #5, either 12" or 6" OC in 6" of 'crete would hold most anything we drive. The tech bull on EPS was interesting, but coming from the lion's den I would expect that. It may be 100% true, but I wonder. EPS is not something to be used under slabs, typically, but is apparently good stuff for roofs that don't leak. That said, Passivhaus projects are using as much as 16" below slabs!