My husband and I are insulating our garage. What do we do when come to the circuit breaker box, with all the wires, and even the propane gas line? How do we insulate around these items?
Thanks for your question and welcome to the community!
It sounds like you have the sheetrock/walls down so that the studs are exposed.
Depending on what the local building/electrical codes call for in your area, you can place your R-13 or R-19 wall insulation as close as you can to the box itself.
I have heard of electricians putting Great Stuff insulation foam or duct seal in the holes where the knockouts for the wires come into the panel, but unless you have draft issues there, I would leave it as is.
If you did decide to seal the holes, you may need to do future re-wiring and if the foam is in the way, it can make it hard to do that.
So in conclusion, only seal these holes if it would create a draft. Cut the drywall as close as possible to the panel, not the cover (as the cover will overlap the hole).
If you wish, you can place backer rod foam or caulk around the box before the cover is on, but do not put any sealant or insulation directly beside or behind the cover panel. This will make future removal of it next to impossible if that was done to it.
Install the insulation as close to the outsides of the panel, and refer to any local building/electrical codes if you have other specific questions .
Hope this helps you out, and let us know if you have other projects you and your husband are working on in the near future.