Certainly, if the plenum isn't insulated.Originally posted by nyrfan
Where the handler comes though in the attic is the 100% not “insulated” attic above the garage, could the gain be happening there on the supply plenum as it’s called?
Florida Building code requires that the garage plenums be sheet metal up through the point where they penetrate the wall / ceiling, so I assume yours is? I also would have thought that it was insulated all the way to the duct terminus. Is it not?