@SirNuke All of the comments saying spray foam are technically correct - that is the easiest way but it will look like orange crap. Some people mentioned steel wool - avoid that because it rusts and will end up looking like orange crap. Find some “excluder mesh”, which an inexpensive product sold to the pest control industry - it is a nylon mesh with reinforcing fibers…think Brillo pad stiffness. Stuff the gap to fill it then use silicone sealant to finish it off.
I would say the expanding foam would still be preferred. Just don’t go crazy with it. Then before it’s fully cured, cut it back flush. Wait for it to dry then caulk to cover/seal.
That’s a good suggestion, I was looking at stainless steel wool and wasn’t finding a lot of great options.
Expanding foam all day long
Is that an actual thing? I diy’d some of that by shoving a bunch of steel-wool into the foam while it was wet. Seems to have worked.
For context, this is leading to my AC unit. While hanging a light above my workbench, I noticed daylight coming in from the wall where there shouldn’t be any. It appears a previous owner had pulled back the insulation and forgot to put it back - shudder to think how much money that’s costed me over the last two years. Would like a hardier seal than insulation to stop water and mice, but not sure what is required.
Really depends on access. Can goy access it from the backside? Quick and easy, but a little messy, expanding foam.
Okay, I know that’s a typo, but I’m cracking up at the idea of you asking about unauthorized access by Jewish people.
It’s super awkward but I can get to it from inside the house (between insulation and hole). Going to have to move my workbench but so be it.
Any direction on the type/brand of foam I should use? I have a can of fireblock to seal ethernet runs from my basement to main floor, though it’s probably seized up by now.
I would use fire block since normal expanding foam is flammable. If I could get behind it, I would see if the hole was excessively large and if so, cut a piece of OSB to fit the space with a hole the correct size in it. Then I would bisect the piece of OSB (making sure to bisect the hole) so that I would be able to get it around the cables and refrigerant line. If the hole isn’t excessively large, fire stop caulk the penetration and insulate the best you can.
Spray foam on the inside. Silicone on the outside.
Duct seal.
That’s pretty universally what I have seen used here. This stuff for those unfamiliar.