The attic is the huge area that is under the roof as a barrier between the outside conditions and inside (Vented VS Unvented Attics Advantage and Disadvantage). The roof surface protects the home from the rain, sun heat, snow and all weather conditions but it also have an impact to the interior conditions too. That depends of the insulation installed right bellow the roof . In the past most of the roofs and attic spaces were vented, so people realize they have huge amount of loss of the energy and money because of it.