Hi All,
I searched the archives and didn’t come up with what I’m looking for…
I plan to mount an electric subpanel in my attached garage to feed the garage circuits as well the circuits for a new room being built above the garage. The feeder wire from the main breaker will run thru my basement, and up through a garage wall shared with the house (hence the wall is currently drywalled).
My question is twofold:
1. How to mount the subpanel? Mount it on the drywall surface, lag screwed to a stud? or Do I have to cut the drywall and flush-mount it (inset the subpanel in the wall). The latter would be much more difficult to get wires to.
2. If I mount the subpanel right on top of the drywall, how do I properly get the feeder and circuit wires from inside the wall to outside the wall to where the wires enter the subpanel? I imagine I can use flexible metal conduit once the wires are outside the wall to the subpanel top or bottom, but how do I properly transition the wires from inside the wall to outside the wall? Wires entering/leaving the subpanel from the back side of the subpanel is maybe an option, but I don’t think there are enough knock outs on the back of the subpanel to do this.
If this isn’t clear, I can come up with a picture or something to help explain.
Thanks in advance,
E.
Replies
I don't doubt that your very capable but I think this task is one that you would be wise to let an electrician do. I know it's expensive but then you don't want to risk burning your house down because you incorrectly wired a subpanel. Your questions tell me that your experience doesn't match your desire. No shame in that but the intelligent move here is not to do it yourself. A lot of construction can be done without prior knowledge or experience and the consequences are not life threatening, but anything electrical shouldn't be attempted unless you know what you are doing. A screw up here can mean killing yourself, your wife, your family , the dog and losing your house and not having insurance to cover the damage. Please get a professional for this particular project and come back to this forum for advice when a less critical project is staring you in the face
Woodway,
Thanks for the response, I appreciate the nature of your response, but it doesn't answer my question.
In the past I have done many residential wiring projects, including installation of a subpanel, all of which have been done with permits, rough and final inspections. I feel capable and qualified to do the work.
What I have not done before is mount a subpanel on an existing finished wall. That is the reason for this question.
Can anyone help with the proper way to do this? My intention is to clear my plans with the building inspector (I already have the electrical permit), but I want to understand the proper way to mount the panel in this particular situation, rather than just give it my best guess.
Thanks in advance,
E.
Mount a sheet of plywood on the drywall from the bottom of the panel to the ceiling.Treat it like a panel in a basement.But you still have to trim out around the ceiling holes one way or another.other you can use conduit sleave the cables from the ceiling to the box. But if you have more than 2ft and have multiple cables in one conduit you can get into derating problems.But what i wrong with opening up the wall and patching the DW afterwards.
> But what i wrong with opening up the wall and patching the DW
> afterwards.Well, you'd have to frame it out like a window opening. And it would reduce the fire rating of the wall.
If ignorance is bliss why aren't more people
happy?
Thanks Guys,
It definitely sounds easiest to cut out the drywall and mount the box inset between the studs, even if horizontal blocking is required, as DanH says.
My only concern with doing this is the difficulty it presents if I would ever want to add an additional circuit in the future, but perhaps with careful planning, this wouldn't be an issue.
As always, thank you for your time.
E.
Careful planning would include adding a couple of spare circuits.
~Peter, the Crossword Puzzle Editor for FineHomeBuilding
My only concern with doing this is the difficulty it presents if I would ever want to add an additional circuit in the future, EBrandt,Something you could do to take care of this problem is to have a piece of plywood "let in" just above the panel say 6 in x 16 in (flush with drywall). Unscrew, and extra circuits are a snap. If you do it neatly, paint it to match - it'll look fine.Another way we have done it is to run an empty pvc conduit for such occasions.Fz
I plan to mount an electric subpanel in my attached garage to feed the garage circuits as well the circuits for a new room being built above the garage. The feeder wire from the main breaker will run thru my basement, and up through a garage wall shared with the house (hence the wall is currently drywalled).
@@
Since the feeder is coming up thru a stud bay and you have more circuits going to a room over the garage, what is wrong with installing it in a bay? All ours have been mounted in bays. At times we frame a chase overhead for the circuits. Usually just cut two slots in the top plates for the circuits and lube them.
Planning to surface mount EMT in the garage for those circuits? (My favorite approach) You could surface mount a wiring gutter for them to run into.
The ToolBear
"Never met a man who couldn't teach me something." Anon.
>>what is wrong with installing it in a bay?
Nothing wrong with installing it in a bay.
As Dan pointed out, if the wall you want to put it in needs to be fire rated (like the wall separating the garage from the rest of the house, of if the garage is close to the property line), then you have an issue with cutting a hole in it for a panel. Other than that, have at it.
"A job well done is its own reward. Now would you prefer to make the final payment by cash, check or Master Card?"
@@
As Dan pointed out, if the wall you want to put it in needs to be fire rated (like the wall separating the garage from the rest of the house, of if the garage is close to the property line), then you have an issue with cutting a hole in it for a panel. Other than that, have at it.
That's right, although I wonder if it is an area thing. Project in the San Juan Islands had all the panels in the garage/home walls. Wondered about that. We don't do that for the reasons mentioned.
Would framing out a panel chase atop the fire wall work? Fire foam the penetrations?
I'd see about running the feeder around to a wall that didn't have those issues.
The ToolBear
"Never met a man who couldn't teach me something." Anon.
>>Would framing out a panel chase atop the fire wall work?
In theory, if you don't touch the integrity of the rated assembly, you can put whatever you want over it. 'Course, you need the John Hancock of your local inspector, so make sure he/she agrees with me.
"Let's get crack-a-lackin" --- Adam Carolla