I put up a 30x32 pole barn 2 years ago. I did 1.5” of spray foam on the walls then 7/16” plywood to cover it up, and painted it white. I’m in NE PA so pretty much same area as OP. LP gas for heat. When in the 20’s outside, it’s 40 inside. Heat gets it to low 60’s. I also have a ridge vent and 1/4” bubble insulation on ceiling so I attribute most of my heat loss to that. Didn’t enclose the ceiling because I was installing a 2 post lift. Walls are 12’ high with scissor trusses so I have wide open ceiling....16’+ to the peak. I know that’s where the heat packs because going up on a ladder after the heat has been running, it’s probably 10-15 deg warmer up there. Closed cell spray foam wasn’t that expensive to do yourself, you can buy the 2 part system....super easy. Kit comes with 2 cans that look like A/C refrigerant bottles with the hoses, spray gun, etc. Head the warnings about open ventilation and wearing a respirator. I had Pioneer Pole Buildings come out for a quote, not bad price but very pushy to get me to sign contract.....like phone calls and emails everyday to see where I stand and when can we get it signed. That pushed me to move on. Glad it did. Lancaster Pole Buildings did it 2k cheaper and got more from them.