Garn insulation

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Chartley

New Member
Nov 6, 2017
2
Revelstoke Canada
We are in the process of installating a junior garn. Looking to see what folks have used for the ridge insulation board under the unit. The installation guide says to use 1 1/2 inch foil faced polysocyanurate foam (Thermax or equivalent) rated to 25 psi, 2 lbs density. We are having difficulty finding such a product in our small town. The ridge pink or blue insulation is available and has a high psi rating, but low operating temp. Any suggestions on what to use? Thanks !!
 
When I was researching rigid foam I saw that there were a few outfits selling it in smaller sizes than the typical 48" X 98" sheet. Just tossing it out there as being smaller would be easier to ship.

That said I know nothing about customs and shipping into Canada.
 
That’s maybe a new practice, as my garn 1900 (1900) gal has been sitting on the regular 2 inch blue foam with no sign of abnormality for 5 years ay the current location and 5 years under the same at it’s prior location. I would think a junior at 1/2 the weight and same temps would be ok, if you had any reservations you could stuff roxul between the foam and the bottom of the unit.
 
I used 2" foil faced foam board from Home depot. Another option is 1.5" blue baord with some reflective insulation on top of that.

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Our home depot has the polyiso as well as the pink, blue, and white boards. Polyiso has a higher R-value per inch but there is nothing special about the 25 psi rating, you can get that specification with white EPS. That's what I used under my shop floor ordered from the manufacturer.

Foil faced is available on EPS too.

I have seen plenty of photos, even on Garn's site, of their units set on pink XPS. You're paying a lot for this thing, call them up and ask.
 
Our home depot has the polyiso as well as the pink, blue, and white boards. Polyiso has a higher R-value per inch but there is nothing special about the 25 psi rating, you can get that specification with white EPS. That's what I used under my shop floor ordered from the manufacturer.

Foil faced is available on EPS too.

I have seen plenty of photos, even on Garn's site, of their units set on pink XPS. You're paying a lot for this thing, call them up and ask.
Hey thanks for all the great ideas! I totally called and asked. There has been a change in practice: they no longer recommend the ridgid pink and blue because the are not rated to the high temperatures that the garn can reach (therefore garn can not guarantee their stability over its lifetime) I ended up finding a supplier (not at the run of the mill harwarestore), a product called IKO enterfoil. Hopefully it will do the trick! Thanks for all the brilliant ideas!
 
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