Adding blow in cellulose to attic
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Hello
I live in mid Michigan with cold winter climates. I am in the process of air sealing all penetrations from my 2nd floor ceiling into my attic space. And also I am venting the existing 2 bath fan vents thru the roof. After that I want to add blow in cellulose insulation on top of my existing insulation. I currently have around 6” deep of loose fill insulation. I have had moisture issue in the past and I have a couple spots of mold showing on bottom side of my roof sheathing. That is why I am doing this upgrade to hopefully fix my attic moisture issues. My roof pitch it 3/12 so there is very little attic space clearance to work in. I’m wondering if I can just blow in cellulose insulation on top of my existing insulation? Or is it a better idea to remove all the existing insulation and then add a vapor barrier and blow in all new insulation on top of the vapor barrier? The space is so tight in the attic at the eaves that I think my only option is for the attic insulation to touch the bottom of roof ply. I have no soffits or overhangs. I’m confident that I have good attic ventilation. My home was built in 1970. I moved in 2014 and I plan to live here forever so I am trying to make the proper upgrades. There is many issues with this house. Any guidance offered would greatly be appreciated. Thank you
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