Attic Ventilation is Often Overlooked

       If you have spots on your ceiling, you know you have a moisture problem. But for others, the problem is more subtle. Our attics are often overlooked when trying to improve the quality of our homes. But it should not be ignored. 

       Adequate attic ventilation is required to prevent moisture problems in the attic, including moist insulation and moisture that can soak through the ceiling.  Here is a guideline: For natural ventilation, provide 1 square foot of vent area for each 300 square feet of attic area if there is a vapor retarder (plastic) in the ceiling. If there isn't a vapor retarder, make sure you have 1 square foot of vent area for each 150 square feet of attic area. Place half of the vent area near the roof peak and half at the eaves. Provide air chutes or use other methods to assure that eave vents are not blocked by insulation and that wind does not enter the insulation, reducing its insulating value.