Q: We have three wind turbines on our new roof. With winter setting in, is it necessary to cover them? Many of our neighbors do not, so as new homeowners, we are unsure.
A: You should never cover wind turbines or any roof vents because ventilation is important all year round.
In the summer, ventilation helps keep a roof and the home it covers cool. In the winter, proper ventilation allows air to circulate in the attic and prevent moisture from condensing on the roof sheathing's underside, which could cause mold, mildew or wood rot.
It also prevents water vapor from collecting in the house. A typical home adds 18 to 20 pounds of water vapor to the living space through normal activities such as bathing, cooking, drying clothes, washing dishes, etc. When this moisture moves from the warm interior air to colder conditions outside (within the insulation layer) it condenses in or on the surface of the insulation, thus reducing its R-Value.
Mike Brazil, Brazil Quality Roofing, Citrus Heights, CA