uncle-al

the well to over insulated house is the outer box the outer only hides the glow of the inner to reduce the heat of the inner it must be vented you have to manage the grow temps to between 80-90 degrees F and often ambient air temp will not cool an enclosed grow in my grow room the heat is removed by an a/c unit cold air in at the bottom hot out the top it is possible that you wont need to use ac to moderate temps i live in a warm climate my grow room will exceed 90 degrees in the dark period easily as it is on the sunny side of the house.

venting into the garage as dump space is not so good the garage will show warmer to ir i reccomend pllumbing the heat to the chimney or ducting the air thru an air conditioner removing the grow heat and placing it in a place where heat belongs exiting an air conditioner or the chimney

there are five sides to the inner box four sides and top, I think that the stairs may function as both a wall and a ceiling but it will insulating and enclosing the insulation, the inside of the inner box, then you have to build the inner box walls and door

__________________
I once thought that I was wrong,
but I was mistaken. Uncle-Al