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How to fix poorly blown in cellulose in ceiling rafters

bfw577 | Posted in General Questions on

My house has poorly blown cellulose in the ceiling rafters in my attic. Using my FLIR there are many areas that are showing significant heat loss especially near the soffits. I am trying to fix it by adding additional cellulose in the ceiling rafter area. The attic has a ridge vent on the roof an 2 eve vents. There are no soffit vents. 

Can I blow cellulose into the ceiling rafter cavities and fill them completely? Some have a slight air gap on the top and some have mounds touching the plywood roof. It was not blown on uniformly. So much mixed stuff out there on to do it or not. My roof gets full sun all day so I cant see moisture being a problem. I attached some pictures as well.

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  1. Expert Member
    BILL WICHERS | | #1

    Assuming this is a vented attic, which it probably is from the look of those pics, you need vent channels between the roof sheathing and the top of the cellulose. If you put vent baffles in, I don’t see any reason why you can then fill up the remaining space in those rafters cavities with cellulose since the vent baffles will hold a vent gap open for you.


    1. bfw577 | | #2

      I dont really have access to put in vent channels. The second picture is looking down the rafter cavities that are like 25-30 ft long. There are no soffit vents at the end. I am thinking of adding additional cellulose and trying to pack it down to leave a air grap at the top. That is turning out to be challenging to accomplish. Have tried with an extension pole. Some rafter cavities have had the cellulose touching the roof sheathing but there are no signs of mositure issues.

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