Insulation touch roof deck
Hello,
I’m in michigan and working on insulating my attic. My attic has no soffit vents (and no way to add them). It has gable vents and slant back vents. My upstairs has a knee wall. I need to add 18 inches of blown in insulation. I currently have 2 inches. I have been working on air sealing and am almost ready to do blown in. Since I have no soffit vents can I blow insulation so that it touches the roof deck in the slanted section? If I can would it matter as far as cellulose or fiberglass touching the bottom of the roof deck? My slanted portion of my knee wall is only about a 12 inch stretch. If I had 2×6 rafters and joists I would probably just add the baffles, but since I only have 2×4 rafters and joists the baffles would only allow me to have a couple inches of insulation. I attached a drawing to hopefully clarify. Thank you
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Replies
I assume the gable vents and the slant back vents are above your 2x4 joists?
Is your attic conditioned?
What currently makes up the walls and ceiling of your attic? 1/2" Drywall?
Do you plan to insulate the knee walls of your attic and if so, how, or are they already insulated?
Is the 12" slanted section insulated or will it be insulated?
walls and ceiling are plaster
attic is not conditioned
knee walls are insulated with mineral wool batt
the 12 inch section has old blown in currently, that 12 inch section is insulated with old cellulose only a couple inches deep