Spray foam insulation is an excellent insulator, but it is also the best sealant out there!
Not only is it insulated, but it is sealed tighter than any material could ever get it!
Most grow house owners prefer to use Shepherd's and spray foam insulation. This is a non organic material, and can be rinsed off when needed.
We installed 1 inch of closed cell spray foam insulation to completely seal this new grow house in Pueblo Colorado!