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Old Balloon Frame with Moisture Problems—Is Rockwool Safe?

LeeMiro | Posted in General Questions on

I bought an old balloon frame home that I’m fixing up. I’m about to insulate the attic wood floor and could use some insight on how to handle the open walls up there. Some are unblocked, which means a lot of air moving up the walls. However, the house also has moisture issues: old flashing, some missing flashing, and damp in the basement due to poor grading and off-pitch gutters. These problems will have to wait until spring, but in the mean time, I’m afraid to seal up the unblocked attic walls. I’m thinking of stuffing R-23 RockWool ComfortBatts in the wall cavities because it’s vapor permeable. Then I’ll cover the wooden floor in more Rockwool or maybe XPS. 


Does this seem safe?


I posted once already but with more questions and didn’t get a reply. I know this isn’t how a pro would do it but the house needs a lot of work (roof, electrical, chimney) and there’s only so much I can take on at once. I’d also appreciate any insight on how moisture and vapor works in old homes when you can’t air seal first.

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