1.   Because attic air is generally dry and hot, it might seem an unlikely place for mildew growth, and, in most cases, it is.

2.   Installing a whole house fan can help cool a house because it will evacuate the hot attic air and draw in cooler, replacement air from the outside.

3.   The warm air in the rooms below the attic rises through the ceiling and mixes with attic air that has been heated by the sun- baked roof.

4.   This draws the hot attic air up through the vents and it is replaced by cooler air coming in from the vents below.