dfielding, A rule of thumb for attic ventilation is 1/150 of the square footage of the attic. Assuming a 2000 sf attic, then you would need 13.4 sf of ventilation total- both intake and exhaust. Adding a power ventilator would pull air from inside the house if you do not have enough intake vents. A 14" x 16" gable vent would provide 1.2 sf of venting adjusted for 1/8" screen. A 2" round vent provides only 2.4 square inches of venting. Dividing the 13.4 sf of venting total would mean you would need 6.7 sf of vent for each intake and exhaust. Intakes should be low in the attic- you could use the blocking between the rafters for round or rectangular vents. Exhaust venting should be as high as possible. If you used only 2" round vents for the intake, you would need about 400 of them to provide adequate intake vent area. Better to try a rectangular version instead. Assuming a 2 x 6 rafter, you could fit a 4" x 12" vent that would provide 36 square inches of venting- this would drop the number of vents needed to 26. Then you still need 6.7 sf for the exhaust. A 2" ridge vent would need to be about 40 feet of ridge. It could also be in conjunction with gable vents if needed. Hope this give you more information to work with. Good luck. Reed B. Turney
|
Linear Mode
