Where can I put my subpanel?

Question

I am installing a subpanel in my attached garage to support a garage heater. The SER feed is coming through the garage wall that is shared with the house, near the bottom of the wall where it is a straight feed through the wall from my unfinished basement and up through the bottom of the subpanel. The feed will be in conduit. I am not sure how to treat the existing GFCI outlet as it pertains to clearances around the subpanel. I have provided a picture of the wall and the subpanel I am using, with measurements. The door trim pictured is the door from the house to the garage. From this viewpoint, the door swings away (into the house). Where would be the most appropriate location to install the subpanel? I do plan to install a piece of plywood behind the surface mounted subpanel. Thanks.

Answer 1

You only need a 30" width, including the panel - i.e., panel could be left, right or middle of that space. So you probably have just enough space to put the panel toward the left and leave the existing receptacle as is.

However, there is, in my opinion, a better solution.

If the receptacle is the only thing on a circuit or is the last thing on a circuit:

• Remove the receptacle.
• Find the other end of the cable or wires going to the receptacle.
• Disconnect the cable or wires at the other end.
• Install the subpanel in the middle of the wall on top of plywood that extends over the two middle studs.
• Add a GFCI in a metal box attached with a nipple to the subpanel and attach to a new 15A or 20A breaker.

If there are other things connected to this receptacle (either pigtailed off "line" or separately from "load"):

• Remove the receptacle.
• Find the other end of the cable or wires going to the receptacle. (That is, the source power or "line").
• Disconnect the cable or wires at the other end.
• Install the subpanel in the middle of the wall on top of plywood that extends over the two middle studs.
• Add a GFCI in a metal box attached with a nipple to the subpanel and attach to a new 15A or 20A breaker.
• Route the existing "output" cable/wires that used to go to the receptacle either into the panel (if they were pigtailed off "line") or into the receptacle in its new location (if they were connected to "load", so that you don't need another GFCI).

Answer 2

The first priority with panels is working space. Panels need a "working space" the width of the panel (but at least 30"), 36" deep (standback distance), and 6'6" tall. This space needs to be kept clear at all times.

So subpanel location is all about finding a location where this will remain clear naturally without having to paint yellow and black zebra stripes on the floor or the bad vibes of someone having to be a "working space nazi" and scold anyone who tries to store things there.

A hall or threshold is ideal.

There are no particular rules about receptacles near panels. Especially since the socket is flush-mount and you are planning to surface-mount the subpanel. Some people get hassles about bulky inlets being inside the working space but shouldn't be a problem for a simple outlet.