Connecting Rough In To Sub Panel and Main Panel Detached Garage

[Landfall0158]

I have a newly built 26x26 detached garage in Henrico, VA and it's feeling like things have been planned out well enough. I had a local company come out to dig a trench and run a 2" pvc conduit for feed line to the garage and a 1" pvc conduit for internet. I'm feeling like I want to connect the subpanel myself just based on how some of this work was already done but based on the rough in it's not seeming that straight forward. I may call another electrician to see what they think.

My main panel is 200 amp. I'm planning on running a 125a subpanel with 1/0 AL wire with a 100 amp main breaker in case I do upgrade my main service.

The rough in at the subpanel location is coming out just in front of the wall. This is to left of the garage door. I'm planning on drywalling. There's also a stud right in the middle. I'll have to check with my builder on the stud spacing there.

Let's say I remove the stud and recess the panel I assume I can use a 45 to bring the conduit. under the subpanel. Otherwise I could build/extend a false wall to have it be recessed.



Now on the main panel side, things seem harder. They've come into a cinder block stem wall. The main panel is recessed in stud bays.

It's not clear me to what the best route to the main panel is here. Do i use another LB and then go back into stud? Then i have to have a junction box to go from THWN to SER?






Am i missing something here because i'm not an electrician or was the routing done in a way that makes life harder?

 

[larry4406]

I will let the sparkies answer your electrical questions.

Your detached garage wing wall adjacent the garage door is likely a shear wall. Study your framing plans. I’m thinking a poor choice of panel location due to potential shear wall.

 

[matt_i]

It looks like the 2" comes up fully proud of the stud wall. Can you slip a piece of drywall behind it(?). Its not the finest work, but if so, you can bend (flex) the conduit over several feet to glue into a male thread box adapter that will hit a knockout in the bottom of your subpanel.

Also...you could also core out what you have there, glue in new conduit stub(s) placed in a better spot, it's relatively easy to fit the pipes back to existing. (I think!). Underground you can flex quite a bit and nobody will care.

Surface mount deserves some thought about how the wiring will leave via the top side of the box and be secured if NM.

 

[wyliesdiesels]

not sure you will be able to safely remove studs on that garage wall. i would check with the GC first. it may be structural.

as to the main panel, I would have come in the back side of the main above or below the meter pan. as it is now, it will be a real pain to get into the panel with conduit. you could still reroute on the outside wall and thats what i would do

FYI- all that stuff you have in front of the panel violates the NEC required clearances. i would move the stuff

 

[mm08822]

Whomever trenched that didn't help you by making a hard 90. It could have been 2 45s or even arc'ed.

At the main panel you could put a horizontal LB flush with the block wall pointing left (to the panel). Run a few feet of conduit and add a 90 pointing upward. From the 90, add a female connector. Run sealtite into the bottom of the panel using a 45 degree connector. May need to notch the sillplate.

Back of the panel would have been much easier.

At the garage, it looks like you are stuck going with a surface mount panel. Otherwise reworking that conduit gets ugly!
Figure it out before you pull any wire.

Next time provide some space between conduits.

Someone with a heating blanket for conduit would be helpful to make offsets.

 

[Landfall0158]

Man, I thought I hired professionals. I had mentioned the placement of the subpanel to the electrician and asked if that made sense and they said it would be okay.

So I think building a false wall for the subpanel will make things easier on that side. At least one benefit of that is i won't have worry about going through a structural top plate.

For the main panel. It seems like i have a few options

1. Reroute on the outside with a sweeping elbow and then a LB right under the meter box in the small cavity between main panel and the bottom plate.


2. LB to the left -> sweeping 90 -> sealtite to 45. I'm having a hard time finding a short run of 2" sealtite on home depot or lowes? Is this something they sell by the foot in store? And in the 2" its really expensive for any length i am seeing.


3. Option 3 is the nuclear option where i just trench a new line to the right side of the garage.....

 

[Landfall0158]

FYI- all that stuff you have in front of the panel violates the NEC required clearances. i would move the stuff

I'll move that stuff thanks for the heads up.

 

[wyliesdiesels]

i would not do option 2 on the main. option 1 is way better

option 3 for the garage, thats your call but youre most likely locked into surface mounted panel unless you move it

 

[dscheidt]

Panel location in the garage is fine, you just can't recess it in the wall. Surface mount it or build a wall in front of the studs.

As for getting to the main, since you've already got a penetration, I'd try to make it work.

How about a largish pull box on the wall. Conduit from outside enters in the lower right corner, conduit to the panel leaves on the top into the stud bay to the right of the panel, and enters from the side. Depending on the exact details it might be possible to bend a piece of conduit to fit, or you might need a unilet of some variety. I'm pretty sure I could make a piece of 1 1/4 EMT work, which would take copper big enough for your proposed loads. Splice to aluminum in the pull box.

 

[mm08822]

Man, I thought I hired professionals. I had mentioned the placement of the subpanel to the electrician and asked if that made sense and they said it would be okay.

So I think building a false wall for the subpanel will make things easier on that side. At least one benefit of that is i won't have worry about going through a structural top plate.

For the main panel. It seems like i have a few options

1. Reroute on the outside with a sweeping elbow and then a LB right under the meter box in the small cavity between main panel and the bottom plate.


2. LB to the left -> sweeping 90 -> sealtite to 45. I'm having a hard time finding a short run of 2" sealtite on home depot or lowes? Is this something they sell by the foot in store? And in the 2" its really expensive for any length i am seeing.


3. Option 3 is the nuclear option where i just trench a new line to the right side of the garage.....

Better pull the panel cover off and see if there is room for option 1. Looks like the bottom of the meter panel is at same height as main panel bottom.

Option 2. Go to a supply house and get 3 ft and a 45 degree connector and a straight.

Whomever trenched this surely didn't think ahead for the main panel connection. It seems like every garage/pole barn, everybody has to hit the closest point of that structure which usually puts the sub-panel in a crappy place.

 

[matt_i]

my guess....purely a guess....they were planning on putting a 2-1/2" holesaw thru the 3-1/2" side of the stud to access the panel sidewall knockout with a ******. Getting spindly there on framing but it basically fits with the work already shown. Use an LB from the ****** thru the stud to turn out on a 45 degree down, then a 45 degree ell to point straight down, then a 45 ell parallel to the wall plane fit to another LB on the stub going straight out.

 

[Landfall0158]

Isn't max allowable hole size 40% of width? So 1.375 inches? But seems like a stud shoe would be okay then. https://www.homedepot.com/p/Simpson...zed-Stud-Shoe-for-2x-Lumber-SS1-5-R/100375338

I'm going to try and get some other electricians to come out and quote the remaining work and just give feedback on how they would do it.

 

[Bad Habit]

Why not extend the conduit straight up on the outside and penetrate higher than the panel. Then (assuming no or few obstructions) wrap it around the studs and then feed into the top?