As many as four different trades must coordinate on a new home to properly ventilate the attic. A lack of coordination results in most attics being poorly ventilated. While attics and crawlspaces are physically connected to a home, the air, moisture and pollutants in these spaces should not be exchanged with the rest of the home. The attic and crawlspace ventilation must be separate from the ventilation that provides fresh air to the living space.  MD Approved; VA Approved