Should lean-to be insulated?

[jsundin65]

24x40 garage with 12x40 leanto on side. 10’ walls in lean. I’ll enclose back and sides.

I’m spray foaming interior of building. Does the lean need vapor barrier of will it equalize with air temp and I won’t worry about rain from inside the lean?

Anyone with drip problems in their leans?

 

[tmp]

You’d be wasting money insulating the back and sides if the front is open to the air. Similarly no vapor barrier needed since it’s able to dry to the inside and the outside and there’s no real vapor drive since it’s not conditioned. If you’re putting a cladding on the back and side walls I would definitely put a weather barrier on the sheathing (tyvek or similar).