What is the thermal envelope?
The thermal envelope or closed attic approach is a new development for hot and humid climates. A growing body of research from ASHRAE, D.O.E., FSEC (Florida Solar Energy Center) and the Building Science Corporation, suggests that ventilating an attic may be counterproductive. The traditional methods of attic ventilation (gable vents, turbines, soffit and ridge-vent assemblies) do eliminate a small amount of heat, but this method tends to bring, into the attic, large volumes of moist air.
