Insulating rim joist – with wiring attached to it….
As I continue on my insulating journey in my new-to-me home (after plugging the hole in the siding where the AC lines come in), I have been going around the basement and pulling out the fiberglass batt insulation that was stuff against the rim joists and installing 2-inch rigid foam board and will spray foam around the edges.
As I was going around the basement and pulling out insulation I came to the spot right above my electrical panel. This happens to be on the short side of the house, so this section has the floor joists running parallel to the rim joist. when I pulled back the fiberglass, I found several neat rows of electrical wires stapled to the rim joist. How can I better insulate this section? I am assuming I can’t put the foam board over the wiring, and I haven’t tested if there is enough slack once I remove the staples to slide the foam board under the wiring so it is flush against the rim joist. Any thoughts, or is this section just going to have to be batt insulation, and maybe foam/caulk the joints for air sealing before putting the batt(s) back? The panel is in the front corner of the house and the wiring runs to about midway (15′ or so) before turning and running along the supporting steel I-beam and splitting up throughout the house.
GBA Detail Library
A collection of one thousand construction details organized by climate and house part