We felt an instant buffering from the cold as we’re were installing it in our porch It’s a cold 50 deg outside and 69 deg inside. It’s been installed for fifteen minutes and the porch is roughly 65deg now, and there’s no heat out there (just the door to the house open).
I have too many houseplants and little room to fit them inside during the winter, so this will house them for cold season (with heat pads), and I can start my seeds earlier now (especially the marigolds) with the porch a converted green house!!