Ventilation is used to manage moisture and heat in attics and crawlspaces, yet most ventilation is undersized and poorly incorporated.  As many as 4 different trades must coordinate on a new home to properly ventilate the attic.  A lack of coordination results in most attics being poorly ventilated – leading to mold growth and structure deterioration.   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 fresh air exchange to the living space.