Replacing insulation in 4″ exterior wall holes
We’re having our house rewired. So far they’ve made three 4 inch holes in the drywall on outside walls. They then poke around the spray foam insulation to fish the wire, etc.
How can I fix the insulation before patching? It’s only 3 holes and then the space just outside a few outlet boxes. Great Stuff would just expand to much around the electrical boxes I think. Filterglass is my only thought for just three 4 inch holes.
I’m going to get a can of the orange Great Stuff for where they poked holes in the rigid foam rim joist insulation to fish wire as well as every penetration in the top and bottom plates of both interior and exterior walls.
Suggestions overall, and especially for these 4 inch holes, appreciated. Thanks!
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I forgot the photos, here are 2 good examples. These are all the big holes on exterior walls so far.
Jeremy,
I'll respond to your post to give it a bump. Are you asking how to patch the large holes? There are lots of resources online on that topic, but maybe I am misunderstanding your question.
I'm asking what insulation to put in the hole before I patch. I'm good on the patch end. Just put in a small piece of fiberglass or am I over thinking it? Thanks!
Jeremy, if the spray foam against the exterior sheathing is intact, you could just stuff the holes with fiberglass or mineral wool (Roxul/Rockwool or similar). Or use low-expansion spray foam. For such a small area, they will all insulate roughly the same.
Low expansion foam is typically marketed as "window/door" foam. The Great Stuff version is a blue can.