Hey passthat,
Nice grow you got going, I would get some mylar and line the walls on four sides and on the floor with it.For the floor get a picse of plywood to put the mylar on so it stays flate.In my closet I glued the mylar to foam broad and then lined the closet with it.The foam broad is an insulation they use to insulate basements and crawl spaces with.
Nice grow pass that shit