I want to blow in insulation in my roof. I understand that I’m supposed to put in baffles along the eaves before I do it so I don’t cut off the air flow at the eaves, but my roof is very shallow, and I can’t get close to the outside edges. Any suggestions on what to do?
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How deep is the roof cavity at its highest?
There are two sections to the roof.
I can just about stand up in the center of the main section, so it's about 5'6" high.
I also have a gable end in one corner of the house with a blind attic. I'm going to be reshingling in a few weeks, so I'm going to take off some of the plywood decking to get into it and blow in insulation. At the center, this attic is probably not two feet tall. It has vents under the eaves, but there is no venting on the roof. I have no idea what I'm going to find in there when I open it up, but I wouldn't be surprised to find no insulation at all.
Since you're re-shingling you can lift boards at random to get at all airsealing sites. If it has no insulation-all the better to get at air leaks and seal them. With proper airsealing, little ventilation will be needed since you've stopped the warm, moist air from getting to this attic. After airsealing, I'd either (1) fill the cavity with cellulose (a little overkill at the high point) but if air and moisture can't get in from the house, then no need to get them out with venting!! or (2) try to get the vent channels in and blow at least R40 in. Just use soffit vents on this roof.
Don't forget that as you make the house more airtight and energy efficient, you need to take care of house moisture by drying it up and venting the interior.