Rim Joist Insulation Installation and Existing Foam Board
I attempted my first home project as a home-owner over the weekend. I guess you can’t call it a fail, because it didn’t even get going. After researching for quite some time (with limited googling abilities, mind you), I haven’t quite found any information that answers my question(s). I’ve decided to ask you fine folk as a last attempt before doing what I probably should have done in the first place and hired a contractor.
Here’s a little information on the house:
After noticing quite a bit of heat loss around the windows (which are original) and the front door (which could use some weatherproofing) over the winter, I wondered what else could be done to help save money on my electric bill. I spent $75 for what the local energy company calls an “energy assessment plus.” Overall, I think it was worth the money. I‘m sure most of you are familiar with the process, so I will save you the explanation of everything he did and cut straight to the point.
Of the list of recommendations, he suggested insulating the rim joists in the basement first, and said it could be done without hiring a contractor for a few hundred dollars. Not being the handiest of men, I still felt confident this task could be completed. The plan was to clean out the rim joists, cut 2” XPs (side note: I will reconsider materials used since finding this site and considering environmental effect; recommendations welcome!) allowing a ½” gap on all sides, and air seal with expanding foam.
You can imagine my surprise when, after having removed the batting around the perimeter of the house, I found what appears to be 1” iso insulation already installed. Not that this is even a remotely good excuse, but I’m guessing the inspector missed it as there was still batting below the first floor.
Given that there is already insulation, my question is whether I can put additional foam board insulation up against the iso, or should I air seal the existing foam board and add batting to the rim joist? I watched way too many home renovations shows growing up to NOT be overly concerned about moisture issues in the basement.
Additionally, the insulation appears to be in pretty rough shape in certain spots. Is filling any obvious hole with a closed-cell expanding foam an appropriate remedy?
I’ve attached a few terrible pictures showing the current state. If any more pictures are needed I will gladly try and clear anything up.
Thanks so much for reading and I appreciate any advice you may be able to offer.
Have a great one,
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