Electrical Question

[BobT]

This may seem like a silly question but my 25+ years of electrical experience was primarily focused on industrial packaging machinery design and installation and not residential wiring. 

 

My neighbor is building a new unattached garage. It will be insulated and finished on the interior but he wants to run the electrical circuits after finishing the inside so when he asked me, I recommended putting his wire inside conduit, either EMT or rigid PVC. To do this I told him that he'll want to use stranded wire instead of solid core as this will be far easier to handle in conduit.

Here's the problem. Even though UL lists devices like receptacles for stranded wire, In my opinion, stranded wire should not be used on screw terminals unless they include saddle straps or clamp/pressure plates. Wrapping stranded wire around terminal screws is a recipe for disaster. Finding receptacles that incorporate saddle straps is not easy. A solution that I thought of would be to use Stacon connectors but I'm not sure this would be permitted per NEC code and we haven't found that answer yet. We are referencing the new 2020 NEC and he will have his system inspected accordingly. Does anyone know if it is permitted by NEC to use crimp-on connectors such as the one pictured for fastening the stranded wire to the devices?  Also, if you could point me to the section of code that applies it would be most appreciated.

 

About the only other option that I can think of is to used solid core pigtails to facilitate the connections to the end devices. 

 

Thanks!!!

[delcecchi]

Why did you think conduit was necessary?   Can't you just use regular NM in a garage?  That's what every one I have seen has, including mine.  

[Cooperman]

Bob,  the best method is to pigtail all your outlet devices with solid wire of the same gauge. Then wire nut the stranded runs to the devices. 

[BobT]

48 minutes ago, delcecchi said:

Why did you think conduit was necessary?   Can't you just use regular NM in a garage?  That's what every one I have seen has, including mine.  

You mean strapping Romex directly to the walls? Doesn't that violate the need to protect them from damage? Plus, I figured it would be a much nicer, more professional finish.

Edited January 6, 2020 by BobT

[BobT]

5 minutes ago, Cooperman said:

Bob,  the best method is to pigtail all your outlet devices with solid wire of the same gauge. Then wire nut the stranded runs to the devices. 

That's where I was headed. Thanks.

[delcecchi]

4 minutes ago, BobT said:

You mean strapping Romex directly to the walls? Doesn't that violate the need to protect them from damage? Plus, I figured it would be a much nicer, more professional finish.

I don't know about damage. Usually on the side of the studs.   I see it often, but I don't know about the code requirements.

[rundrave]

If I was building new I would skip the conduit. As suggested run the wire right along the studs with these

 

I am not sure what the advantage of doing EMT conduit would be? Just seems like the receptacles etc would get in the way or risk being bumped or hit with something. And I would get tired of looking at all the lines.  I would run the wire along the studs and get all the receptacles flush with the wall just like a house.

 

After the new garage get gets framed, just run all the wire, get it pig tailed and then get it inspected. Then get the walls and interior insulated and finished.

 

I would use 12  gauge wire with a 20 amp breaker (outlets etc), and 14  gauge wire with a 15 amp breaker (lights). Also since the receptacles are in a garage, they'll have to be GFCI protected. 

[Down2Earth]

I second rundrave.  Don’t forget to tell him to put outlets in the ceiling for the garage door opener(s), hotdog heater, stereo system if up on a shelf, I’d also put in a ceiling fan box or two in right away even if he doesn’t think he’s going to use them.  If the building is going to have steel I believe code is conduit or this type of wire needs to be used.

[Big Dave2]

6 hours ago, delcecchi said:

I don't know about damage. Usually on the side of the studs.   I see it often, but I don't know about the code requirements.

 

Re-read the post. I believe Bob is talking about finishing the walls first and adding electrical later but I'm not sure why anyone would want to do that.

[PurpleFloyd]

15 minutes ago, Big Dave2 said:

 

Re-read the post. I believe Bob is talking about finishing the walls first and adding electrical later but I'm not sure why anyone would want to do that.

That’s a lot more common on commercial or agricultural buildings. Most cities require conduit but in ag you can run pvc. 

[delcecchi]

39 minutes ago, Big Dave2 said:

 

Re-read the post. I believe Bob is talking about finishing the walls first and adding electrical later but I'm not sure why anyone would want to do that.

Sorry I missed that totally.  So, surface wiring?   Then I have no idea what code is.

[BobT]

Yes, my neighbor wants to surface wire the interior. I had already suggested completing the electrical work before finishing the interior. I'm not aware of any code that would forbid this option and if I understand the 2020 NEC code correctly, EMT or PVC would be acceptable. There is very little that I can find regarding residential detached garages. Article 511 covers commercial garages, but this is not a commercial garage. 

 

He wants to do this himself, which is okay as long as he gets it inspected properly.

Edited January 7, 2020 by BobT

[delcecchi]

I did a brief search, and looks like there are several alternatives, but this is way outside my area of expertise.  Exposed wiring seems like a strange choice but to each their own.

It did look like there is special wire that is recommended for conduit.   Not sure if it is required or not. 

Edited January 7, 2020 by delcecchi

[BobT]

7 minutes ago, delcecchi said:

I did a brief search, and looks like there are several alternatives, but this is way outside my area of expertise.  Exposed wiring seems like a strange choice but to each their own.

It did look like there is special wire that is recommended for conduit.   Not sure if it is required or not. 

I don't think it would be good to leave the wiring exposed and that's why I suggested the conduit. Yes, we need to study the implications of using conduit.

 

It should be noted that he has already begun installing the wall and ceiling steel. I told him he would need to calculate the appropriate lumens for lighting, provide branch circuits for 120v receptacles, 240v receptacles for welder, ceiling fans, any heating systems he plans to install (he's designing it for in-floor heat), and proper outdoor lighting at entrances. 

Edited January 7, 2020 by BobT

[BobT]

I think part of his thought process is that the building is built into the side of a hill so the bottom seven feet or so is block walls so running the wiring in conduit would be about the only alternative for his receptacles and other outlets at accessible heights.  

[delcecchi]

Ok, that makes sense.

[delcecchi]

He isn't insulating the block?  Just thought of this.

[BobT]

Yes, it has been insulated.

[delcecchi]

Must have been on the outside because otherwise he could have put NM under the insulation.   Just trying to figure out why he did what he did.    I am assuming he had his reasons since seems like conduit would be more work and expense than Romex.   

[BobT]

The block walls will not be covered. Only that part above the blocks will have a finished interior wall.