Are ventilation channels effective in creating a vented attic?
I have been reading the site for a year trying to figure out how to insulate my older 1 story home’s attic. There are a number of articles about insulation behind knee walls and the issues of creating an air barrier and getting enough insulation in. And then not defeating the fiberglass by wind washing. I haven’t seen any articles that discuss in roof venting low down. I have almost zero soffit vents and poor flow patterns should soffit vents be installed. My new roof goes on in a few weeks, and the plan is a ridge vents and inflow on the roof low down. Then I expected to insulate the floor and top off the fiberglass with a thin layer of rigid insulation to prevent wind-washing. Do I still need baffles? There are no duct works or HVAC in the attic.
I can crawl pretty deep into the space between the floor of the attic and the exterior wall but it’s no picnic.
Thanks for the advice,
Rachel
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Replies
Rachel,
Baffles are used to allow air to enter at the eaves and to direct it up the roofline while preventing insulation from clogging up that area. Blocking (wood or rigid foam) is typically used between the rafters and from the top plate to the baffles to prevent wind washing. If you have another method for allowing air to flow from the intake to the exhaust vent and/or for preventing wind washing, then you don't need baffles.