Retrofit Wall Insulation Behind Stucco?
Hello, I recently had a home energy audit that revealed my 90 year old south Minneapolis home does not have any wall insulation in the exterior walls. This is insane to me. They recommended dense packed cellulose as a solution to the problem.
However, I see comments on this website about moisture building up and the consequences of a wet stud cavity. I am sure imperfections in the stucco lead to water in the stud cavity from time to time.
Who is right? Without pulling off the interior walls or exterior stucco, what is the best option for insulating my walls?
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Replies
Hey Carl!
I've seen many homes like that from the 1920s where cellulose was added in the early 80s and I've never seen problems when I opened up a wall. Yes, with air moving from hot to cold in winter, moisture will accumulate in the wall with cellulose, but it does a good job of spreading it out and drying during the standard hot MN summers. If you've had a blower door test done and it was over 4 ACH, then you'll dry fine. Just make sure they have a thermal imaging camera to prove to you all the stud bays were really filled when the job is done. When it comes time to properly air seal the house and insulate from the exterior, you'll be glad you had it done.
Brilliant response. Thank you for your time!