What are the proper fasteners and method to mount electrical panel onto exterior of house? Also have two knockouts at bottom of panel for bringing circuits into house. What size hole is recommended for roughly 12 circuits per hole for an average house? I am not sure what parts to buy for those holes that go through siding and into house.

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    What make and model is your electrical panel? Also, what wiring method are you using for the circuits coming into the panel? Aug 13, 2020 at 3:32
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    What size knockouts are in the back of your panel most folks use those to size the bushings or nipples. there are max fill numbers it’s not just the number of wires. When I punch a panel to go into the wall behind the panel I usually punch 2 holes for 2” bushings that usually will provide enough room on panels that don’t have knockouts.
    – Ed Beal
    Aug 13, 2020 at 5:01
  • What is your house made of and what kind of siding (if any) do you have? That will determine how you mount the panel. Also, that's a different enough question that you should ask it separately - nobody will look down on you for asking multiple, well-focused questions.
    – FreeMan
    Aug 13, 2020 at 12:32
  • House has T111 siding and 3/4 sheathing for a total thickness of 1-1/4 inches. The knockouts measure 1-3/8, 1-3/4, 2, 2.5, 3 inches. I don't know threephaseeel what you mean by wiring method. I want to bring the circuits from the house through siding using available knockouts in the back bottom of panel. Panel is a homeline 40 space 80 circuit unit.
    – Jeff
    Aug 14, 2020 at 2:23
  • 200amp panel Model #HOM4080M200PRB
    – Jeff
    Aug 14, 2020 at 2:32


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