Dense-Packed Cellulose for Old Walls
I live in upstate New York in a home built in 1958. The home has no insulation in any of the exterior walls. From some research I’ve done, it seems like the only retrofit option available without pretty much tearing all of the drywall down is dense packing the stud bays with cellulose from the outside. This entails removing rows of siding, drilling 2 inch holes through the sheathing, dense packing the stud bays, plugging the holes with a wood cutout, sealing, and replacing the siding.
There seem to be conflicting opinions on whether this is a good approach or not. Some seem to make the argument that older homes of this era were designed/built to be able to ‘breathe’, and by dense packing the walls with cellulose you essentially cut that ability to ‘breathe’ off, setting the stage for mold and moisture issues. Some literally state that this is a surefire way to destroy(!) an old home, and your studs will inevitably rot out by doing this. Sounds pretty scary!
On the other hand, I’ve seen others suggest that so long as there are no known/active water leaks in your home, one could argue that there is little opportunity for the cellulose to get wet in the first place, and so the risk of this rot occurring is relatively low.
It’s worth noting that my house is vinyl sided, and the vinyl is, at least tin my opinion, in pretty good shape. I’m not aware of any major cracks, leaks, etc.
As I mentioned, I live in upstate New York, where temperatures have been below zero degrees Fahrenheit on and off for the past few weeks. So the lack of insulation in my exterior walls currently isn’t doing my utility bill any favors, and i’d really like to do something about it. As aforementioned, seems like dense packed cellulose might be my only retrofit option here, but if that’s going to rot my house out, i’m not sure I want to proceed with that.
I’ve been driving myself nuts here the past few days reading conflicting opinions on this approach on various sites across the internet. I’m doing my best to educate myself, but also understand that sometimes reading too much can just muddy the waters more.
Appreciate any insight anyone here who’s probably way smarter than me on this topic might have to offer.
Thanks in advance!
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