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Pole barn perimeter insulation advice needed

DStyduhar | Posted in General Questions on
Hello everyone,
I was hoping I could get some advice about the perimeter insulation on my pole barn. I have attached a pic showing the skirt detail, with a 2×8 on top of a 2×10 and some temporary midspan 2×4’s to hold things together.
– The distance from the compacted sandrock pad to TOP of upper skirt is ~18inches
– TOP of the concrete will be about 4 inches down from top of upper skirt 18-4 = 14″
– The slab will be 5″ thick 14″-5″ = 9″ inches of fill needed
– The plan is to put about 6″ of crusher run down and then a few inches of 57 on top and do concrete next year.
I purchased 8 sheets of 2″ 25PSI XPS foam last night. Its very difficult to get 1.5″ in this part of NC, its either 1″ or 2″. But anyway, I plan to fasten the foam to inside of these skirt boards BEFORE we fill up the barn but not sure about the following:
Top detail
1. Should I set the foam even with where the top of where the future concrete will be? Should I do a bevel cut at top? Should I just cover the entire skirting and let the foam protrude above the concrete and cut later if needed? I plan on framing the walls in the future and still on the fence about radiant heat.
Bottom detail
1. How far down into the gravel should I run the foam? What about bugs and termites eating nesting in it and destabilizing the base under the concrete? Seems like the most straight forward solution would be to just cover both skirts in a single piece and move on. Really cant get a good feel if bugs are an issue though I have seen where folks wrap the xps in stainless mesh before being buried?

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  1. plumb_bob | | #1

    You plan on insulating from the interior? Seems like insulating from the exterior might be a better option?

  2. DStyduhar | | #2

    I would prefer to insulate on the inside. All the exterior tin and drip edge is already on



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