Added a 2nd treated grade board before adding fill in barn floor. Thinking about adding galvanized or painted aluminum trim to cover seam and hopefully make a better pest wall. Any thoughts?
There are several discussions about rodent proofing skirt boards but I've never read any of them close enough to feel comfortable giving advice. If you use Google to search this site you should be able to find some.
Insulation question Thinking about nailing Owens Corning Extruded Polystyrene 1.5" R 7.5 on purlins. Then cover that with closed cell spray 1" increasing R to approximately 15 and filling any remaining voids. 32x56x14 with posts 8' on center built on Indiana/Michigan line. Any thoughts ?
I can think of two reasons to put down rigid foam before spray foam. First would be to make the steel roof panels easier to replace if ever needed. But I'm not sure this couldn't be done for less money with another material. And some have argued it's not even necessary -- that a roof panel can be removed with minimal yet repairable damage to the foam if needed.
The second reason would be to create an air space and maintain a ventilated roof system. I can see some peace of mind with this but with sufficient spray foam a ventilated roof system isn't really necessary, depending on who you ask.
I bought some Dow extruded foam this summer and it came in at over half the cost (on a board foot basis) compared to installed closed cell spray foam. Of course the Dow would still have labor involved with cutting to size and installing as well as any waste, which is hard to avoid when trimming rigid foam to fit in spaces.
I guess my point being is that if you're considering spray foam anyways then why not go ahead and spray the minimum amount in your area to avoid condensation issues. Unless you're getting a deal on the foam it might not cost that much more.
If there is another reason you're considering the foam then I'm sure somebody here can give you advice on that.
