Box Grounding

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Jimmy7

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Boston, MA
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Electrician
I have to add an outside light fixture to an existing single family residential garage. The garage is sheetrocked, and there is about seven bays between the switch and where the new outside light will be. The homeowner doesn't want to disturb the sheetrock, so I was going to run non-metallic cable in a emt between the bays. I would come out of the bay up high where the switch is to a 4" square and then run 1/2" emt across the seven bays to another 4" square and back into the bay where the light would be. There will be no splices in the 4" squares, do I need to ground the boxes?
 
I believe code says the boxes only need to be grounded when there's a splice.see 250.148

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Use a length of self-adhesive white plastic Wiremold narrow channel with a hole through the back over each hole in the wall.

I've done this with the next-wider size with the new flat 10-3NM for a relocated dryer, except down on top of the baseboard.
 
I would "bond the EGC wire to the boxes" whether required by code or not for the following reasons:
(1) It's both inexpensive and quick.
(2) If there is a fault within the box, it will be detected and trip the breaker.

If what you were asking was a significant difference in time and material, then it's worth fretting about... but it isn't. You're talking a few extra inches of wire and a few extra minutes doing some splicing.

Also, splicing in those boxes will make any future repairs easier because you would then have an accessible pull point.
 
Technically, the NM you pull up behind the sheetrock still needs to strapped according to code, although a lot of guys don't do it.
They'll pretend they follow the rule when publicly confronted about it, but when alone on the job, it gets pulled 20 ft or more without a strap.

With that in mind, as well as the customers opposition to disturbing the sheetrock, you might consider an extension ring on the switch, either 1900 or WireMold, and surface mount the whole way. Either that... or technically you should be disturbing the sheet rock to get your straps in.

These freakin' people and their resistance to disturbing finished work when doing mechanical work. How the heck do they think mechanical work gets done? I swear, we're the whipping boys and the dang drywall takes precedent, SMH
 
LarryFine said:
Sorry, but absolutely incorrect. Fished cables need not be secured.
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I'm glad you pointed this out. You can't really secure a "fished" cable, because then it wouldn't be a fished cable.
It would be a cable installed in a ripped-out part of the wall.

I wish I had a nickel for every length of bx I have fished from A to B.
 
LarryFine said:
Too late to edit above post.

See 300.4(D) Exc. No. 2

Or 334.30(B)(1)
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Agreed, it's been a common practice for over 100 years to fish cables in walls without any need to secure the cables except to the box with a connector.
 
LarryFine said:
Too late to edit above post.

See 300.4(D) Exc. No. 2

Or 334.30(B)(1)
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I'm not sure about 300.4(D) Exception #2 for the following reasons...

300.4(D) Exception #2 reads "For concealed work in finished buildings... where such support is impracticable, it shall be permissible to fish the cable between access points."

Exceptions must refer to their parent section... so what "support being impracticable" is 300.4(D) Exception #2 referring to??

For that we have to refer to the parent section 300.4(D) Cables and Raceways Parallel to Framing Members, which says "the cable or raceway shall be supported so that the nearest outside surface of the cable or raceway is not less than 32mm (1-1/4") from the nearest edge of the framing member..."

Therefore, Exception #2 is referring to "the support" required by 300.4(D), which is about keeping the cable or raceway an 1-1/4" from the edge... and does NOT explicitly permit the exclusion of general strapping requirements.

You may have a point about 334.30(B)(1) though...

334.30 Securing and Supporting is indeed referring to general strapping requirements as it explicitly refers to the maximum interval of 4-1/2 ft and within 12" of every outlet box.

The only argument I could make against this is that (B) Unsupported cables does not use any logical operands to allow for EITHER/OR (1) or (2) to be true, but requires BOTH (1) AND (2) to be true.... but it does not explicitly have the AND logical operand either.

Either way, I disagree that it's "clear" that this is allowable, especially by 300.4(D) Exception #2. As stated, you may have a point about 334.30(B)(1) though, but there's still some ambiguity there.
 
Then there's the whole "it's just sloppy" argument and I'm in that camp, but that's just my personal opinion.
 
flashlight said:
You can't really secure a "fished" cable..
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Sure you can. I do it all the time. I cut my gem box hole. I reach in with my sidecutters and tap the strap to the stud. Then I loop it around and connect it to the gem box. You can also cut an access point to add a strap. It's still a fished cable.
 
Jerramundi said:
I'm not sure about 300.4(D) Exception #2 for the following reasons...

300.4(D) Exception #2 reads "For concealed work in finished buildings... where such support is impracticable, it shall be permissible to fish the cable between access points."

Exceptions must refer to their parent section... so what "support being impracticable" is 300.4(D) Exception #2 referring to??

For that we have to refer to the parent section 300.4(D) Cables and Raceways Parallel to Framing Members, which says "the cable or raceway shall be supported so that the nearest outside surface of the cable or raceway is not less than 32mm (1-1/4") from the nearest edge of the framing member..."

Therefore, Exception #2 is referring to "the support" required by 300.4(D), which is about keeping the cable or raceway an 1-1/4" from the edge... and does NOT explicitly permit the exclusion of general strapping requirements.

You may have a point about 334.30(B)(1) though...

334.30 Securing and Supporting is indeed referring to general strapping requirements as it explicitly refers to the maximum interval of 4-1/2 ft and within 12" of every outlet box.

The only argument I could make against this is that (B) Unsupported cables does not use any logical operands to allow for EITHER/OR (1) or (2) to be true, but requires BOTH (1) AND (2) to be true.... but it does not explicitly have the AND logical operand either.

Either way, I disagree that it's "clear" that this is allowable, especially by 300.4(D) Exception #2. As stated, you may have a point about 334.30(B)(1) though, but there's still some ambiguity there.
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Let it go bro, fishing cables in building cavities is clearly allowed. :)
 
Jerramundi said:
Sure you can. I do it all the time. I cut my gem box hole. I reach in with my sidecutters and tap the strap to the stud. Then I loop it around and connect it to the gem box. You can also cut an access point to add a strap. It's still a fished cable.
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Don't take this wrong but you must have some dinky little hands to position the cable hold a strap in place with one hand and hammer with the other.

Roger
 
roger said:
Don't take this wrong but you must have some dinky little hands to position the cable hold a strap in place with one hand and hammer with the other.
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How can I NOT take that the wrong way? lol This is equivalent to saying "no homo," before you well...
 
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