Passing wiring through a corner

[nate379]

I am working on rough in wiring for my shed. Nothing too complicated, just some outlets, couple lights and 240v for the air compressor.

For the outlets I need to go through the corner of the wall. I framed the building like this but I don't have blocking. (would have been nice now!)

Do I just drill from each side and meet in the middle?


Also what is the story on running wire in stud walls that are to be left open? Do I have to bend the wire so it sits flat against the outside OSB? (less chance it will get used at a hanging rod or pulled on)

 

[Gooch]

I am working on rough in wiring for my shed. Nothing too complicated, just some outlets, couple lights and 240v for the air compressor.

For the outlets I need to go through the corner of the wall. I framed the building like this but I don't have blocking. (would have been nice now!)

Do I just drill from each side and meet in the middle?


Also what is the story on running wire in stud walls that are to be left open? Do I have to bend the wire so it sits flat against the outside OSB? (less chance it will get used at a hanging rod or pulled on)

needs to be in conduit if it's in an open wall, NM cable can't be exposed in open walls..

instead of going through the corner, why not go up and over?

but you can drill from each side, then you need to bend the NM cable and try to fish it around, if you havn't done this before it will not be easy. a needle nose pliers will be handy aswell for this.

 

[nate379]

I could go up and over, but would end up using an extra 8-9ft of wire for each corner.


I might end up just spending the $200 and putting OSB up on the inside then. Seems like a PITA to do the conduit thing!

 

[Gooch]

I could go up and over, but would end up using an extra 8-9ft of wire for each corner.


I might end up just spending the $200 and putting OSB up on the inside then. Seems like a PITA to do the conduit thing!

I'd have to look, but you could use MC cable, but the added cost of it over sheeting the walls wouldn't pay for it.


8-9 ft of wire would be about $3 extra, if you havn't done corners before you will spend atleast 15 minutes on the first one.

 

[Hit-By-Thunder]

I did my corners this way (the one on the left) because of the same reason, running wires and insulating the corner The one on the left does allow for this. I too would run up and over rather than stressing the wire on a tight corner IMHO

Rob/HBT

 

[MrMark]

I'd have to look, but you could use MC cable, but the added cost of it over sheeting the walls wouldn't pay for it.


8-9 ft of wire would be about $3 extra, if you havn't done corners before you will spend atleast 15 minutes on the first one.

I've seen that MC cable used in cheap construction, but I don't think it is code anymore to be run exposed like that. I have looked at this issue in the NEC and I see no distinction with regard to the requirement of physical protection between flex or MC (basically the same thing) and romex.

If someone has a cite that shows that mc is allowed to be run exposed, whereas romex is not, I'd like to see it.

With regard to the question, you strip about 6 inches of the jacket off the romex and then cut off all but one wire. Form the remaining wire into a hook and use that hook to fish through the intersecting holes. Grab the hooked wire with your pinky and pull.

If the run through the corner makes sense (eg not too many studs need to be drilled or going up is problematic) I would go through the corner.

 

[pattenp]

needs to be in conduit if it's in an open wall, NM cable can't be exposed in open walls..

instead of going through the corner, why not go up and over?

but you can drill from each side, then you need to bend the NM cable and try to fish it around, if you havn't done this before it will not be easy. a needle nose pliers will be handy aswell for this.

I may be wrong but I believe NEC 334.15 allows for the exposed run of NM cable as long as it also meets requirements of 300.11(A)

 

[hillbilly1]

Fishing the wire in the corner is not that hard, put a bend on the end of the wire, push it through the first stud and try to hit the hole on the other side, you probably will not get it to go all the way through the second stud due to the right angle, but with a long narrow tip screwdriver, you will be able to massage the wire into a tighter bend pushing it a inch at a time until it clears the corner.

 

[MrMark]

Fishing the wire in the corner is not that hard, put a bend on the end of the wire, push it through the first stud and try to hit the hole on the other side, you probably will not get it to go all the way through the second stud due to the right angle, but with a long narrow tip screwdriver, you will be able to massage the wire into a tighter bend pushing it a inch at a time until it clears the corner.

That sounds like a hard way to go. Why don't you strip the jacket and cut off the wires except for the ground and use that as the hook. Much easier than trying to work cable with a screwdriver.

 

[Steevo]

I know that in the attached garage on my house in Idaho, built in 2007 to current codes and fully inspected, etc., they ran NMB romex around the garage in exposed stud walls for receptacles. It passed inspection that way. I haven't hung anything from it . . . . yet.

 

[Justanoldguy]

Can't see it being difficult to run it through the corner studs.
Been doing it for decades and never once thought it would be a problem.
Maybe people just analyse stuff so much that they create obstacles in their mind.

 

[MrMark]

I think there is some "thought" in the electrician community that mc cable is allowed to be run exposed whereas Nm is not. There is some thought that mc cable does not require physical protection?

I don't know about any of this, but I cannot find one thing in the code to support allowing mc cable to be run where romex could not be run.

I would like to hear from some of the electricians on this, hopefully with a code cite.

 

[hillbilly1]

That sounds like a hard way to go. Why don't you strip the jacket and cut off the wires except for the ground and use that as the hook. Much easier than trying to work cable with a screwdriver.

It takes a little bit of skill to do it quick, but it rarely takes me more than a few seconds to get it through there. (quicker than stripping and fishing for it when you do it for a living)

(By the way the screwdriver trick is used at the hole it's coming out of, you just bend the wire away from the back of the hole to keep it from catching)

 

[nate379]

No not at all, I was just asking beforehand so I had an idea of any tips or tricks is all.

Can't see it being difficult to run it through the corner studs.
Been doing it for decades and never once thought it would be a problem.
Maybe people just analyze stuff so much that they create obstacles in their mind.

 

[6768rogues]

I did my corners this way (the one on the left) because of the same reason, running wires and insulating the corner The one on the left does allow for this. I too would run up and over rather than stressing the wire on a tight corner IMHO

Rob/HBT

I like the left method of framing better because insulation can be put in the corner later.

 

[Gooch]

I may be wrong but I believe NEC 334.15 allows for the exposed run of NM cable as long as it also meets requirements of 300.11(A)

334.15(B) ....Cable shall be protected from physical damage where necessary.......


lists methods of acceptable protection aswell.


exposed romex in a garage wall anywhere below the ceiling will need to be protected.

 

[Gooch]

I think there is some "thought" in the electrician community that mc cable is allowed to be run exposed whereas Nm is not. There is some thought that mc cable does not require physical protection?

I don't know about any of this, but I cannot find one thing in the code to support allowing mc cable to be run where romex could not be run.

I would like to hear from some of the electricians on this, hopefully with a code cite.

330.10(A)Uses Permitted(4) Exposed or Concealed

330.12 Uses Not Permitted (1) Where subject to physical damage


The local inspectors havn't balked about MC being exposed in walls.

IMO NM is easier to damage than MC and in all reality it's up to the AHJ to determine.


all this is out of the 2011 code i've got, but none of it's highlighted so it shouldn't have changed from 2008.

 

[pattenp]

334.15(B) ....Cable shall be protected from physical damage where necessary.......


lists methods of acceptable protection aswell.


exposed romex in a garage wall anywhere below the ceiling will need to be protected.

All I can say is my attached garage when built about 5 years ago originally had exposed romex that ran down from the ceiling on the sides of the wall studs to the outlet boxes and it passed inspection. Not to argue the point but I can't find in the 2011 code that it says in a garage wall anywhere below the ceiling NM will need to be protected. Maybe it's an interpretation thing at the local level.

 

[babzog]

I could go up and over, but would end up using an extra 8-9ft of wire for each corner.!

You can shortcut the corner by going up and over.... nothing says you have to follow the building contour.

 

[Gooch]

All I can say is my attached garage when built about 5 years ago originally had exposed romex that ran down from the ceiling on the sides of the wall studs to the outlet boxes and it passed inspection. Not to argue the point but I can't find in the 2011 code that it says in a garage wall anywhere below the ceiling NM will need to be protected. Maybe it's an interpretation thing at the local level.

IMO, and thats all it is, that should not have passed inspection. but your right, the way it's worded it's up to the AHJ. but anything within reach is subject to physical damage IMO and the local inspector's i have to deal with.

 

[pattenp]

IMO, and thats all it is, that should not have passed inspection. but your right, the way it's worded it's up to the AHJ. but anything within reach is subject to physical damage IMO and the local inspector's i have to deal with.

I just when over to the Mike Holt forum and there is a thread on the subject of exposed NM in residential garages whether detached or attached and it is a back and forth issue as to yes its ok or no its not. I'm done!

 

[MrMark]

I think this is one of the few things that is truly left up to the vagaries of the local jurisdiction on whether it is subject to physical damage.

My point is that the code makes no distinction with regard to mc cable vis-a-vis nm cable as far as one being superior with regard to resistance to physical damage. So if the local jurisdiction does not approve nm cable run exposed then they should not approve mc cable exposed either if they are at all interested in being consistent. If they allow one and not the other, than they are essentially saying they know better than the drafters of the code and that is not going very far with me.

IMO, neither nm nor mc should be run exposed. Either one is easy to damage, and running either exposed looks like a poor job.

 

[Justanoldguy]

No not at all, I was just asking beforehand so I had an idea of any tips or tricks is all.

Nate.
Was really referring to everyone else who made suggestions. Like going up and over and avoiding the corner.. WTF??

 

[walrus]

There is exposed Romex, NMB in just about every house in Maine that has a basement, look in or on the floor joists, lots of exposed wiring. Don't hear alot of issues as result of it.

 

[hillbilly1]

There is exposed Romex, NMB in just about every house in Maine that has a basement, look in or on the floor joists, lots of exposed wiring. Don't hear alot of issues as result of it.

It's the whole "subject to physical damage" thing, which in its self is subjective! It is left up to the AHJ (Authority Having Jurisdiction, in other words "electrical inspector") to make that call. If they decide that the wiring may be subject to physical abuse on the bottom of the joists, (such as a low ceiling height) then they may require furring strips to be run parallel to the wire to protect it if it is surface mounted. Will you have problems with damage running it in the studs exposed? Probably not, but then again something falling in between the studs is always a possibility. Same as walking out in the street and getting hit by a bus.

 

[thdewey]

You can't have exposed non-supported horizontal runs of romex. What they don't want is you shoving tools behind the romex and using the romex to hold your rakes and shovels up. That would pull on the wires = NOT GOOD. If you run it along a flat surface with staples or in an unexcessable area that's OK.

Here is a build pic of my garage. You can see the 8"-10" horizontal OSB running between the outlet boxes. This prevents anything "hanging" from or on the romex. This made the inspector happy. I eventually covered the walls with OSB. I should have used screws to attach the horzontal OSB runs. The ring shank nails were a bear to rip out of the OSB.

 

[Grumpy365]

http://www.electrical-contractor.net.../topics/122256

SO from what I am hearing, clearly this ^^^^ panels is out of code!






I see exposed NM cable and as long as it is supported and protected, I dont think you have a problem.

 

[glockman]

I just had my rough electrical inspection less than a month ago. I have multiple horizontal runs of 12-3 romex exposed at 20 inches above the floor. Inspector asked if I was going to sheetrock, I told him maybe in the future. He then pointed out a couple of runs that were less than 1" from the face of the stud and said I would need to plate them before I installed drywall, then passed my building. Maybe I got away with something. Not likely considering my luck in general.

 

[avc8130]

When I embarked on wiring my attached garage at my old house the first call I made was to the electrical inspector to discuss some of the subtleties.

He advised me that NM was fine in my studded application with NO covering. I ran all of my branch circuits up along the ceiling for my own gratification so I knew dropping wood and storing tools between studs wouldn't be an issue.

When the inspector came, he was so impressed with the neatness of the install that he questioned whether I did it as a homeowner or hired an electrician for "side work".

Bottom line: was this the BEST way to install the wiring? NO. Did it pass inspection? YES. Will it pass inspeciton EVERYWHERE? NO.

If you WANT to run NM exposed in a garage, call your inspector and ask.
ac

 

[EdT]

It seems it's almost all "interpretation at local levels". While all the discussion above is great it will come down to what your local inspector "likes to see". So, why not ask him before you spend a lot of time and effort coming up with something he doesn't like to see or doing a bunch of work on something he doesn't need to see. Locally, the inspectors have been very helpful, but that's not always the case.

 

[nate379]

I have no inspection to pass. Anything under 400sq ft (or around that) doesn't need even need a permit.

I just figure I may was well learn what I should and should not do and try to do it correctly anyway. I'm just going to run the wiring in the studs like it would be getting sheathed and I may decide to insulate and put OSB up on the walls later.