334.15 Thread

[WCEI]

Is there a thread on here already that discusses 334.15(C)? Specifically the justification for this requirement.

 

[Dennis Alwon]

I don't know the real reason for the requirement other than people saying that when the wires are run under the joist then people will hang clothes on them. The larger sizes can handle that??????

Not sure why.

 

[ptonsparky]

Which part? Running Boards?
It references you to 300.4 so guessing that the smaller cables are more prone to physical damage.

 

[ptonsparky]

Am i likely to remove insulation and bore holes through floor joists in a crawl space? I have, but I am getting lazy.

 

[Dennis Alwon]

Am i likely to remove insulation and bore holes through floor joists in a crawl space? I have, but I am getting lazy.

I find it easier to square things off in the crawl. We have always done this anyway so for us the change wasn't a big deal. Actually, NC amended that section.

 

[WCEI]

What I’m really after is the OFFICAL justification the code making panel put forth when this rule was first adopted. (I am not an NFPA member, so I don’t have access to those documents.)

Like Dennis said, it’s ok to hang clothes from a 6-2 or 8-3, but not a 10-3? LOL. Also, if the NM is run though the bored holes instead of being stapled to the bottom of the joist, it’s somehow less vulnerable to damaged when being used as a clothesline?

But, I have a hard time believing that “hanging clothes” was really part of justification for this rule. ptonsparky, I struggle with the idea that anything that might damage a 10-2 or down, would not damage an 8-2 and up.

What brought this topic up, (again), this morning is, if you add a circuit to a home that was wired previous to this code change, does it have to be compliant with 334.15(C)?

 

[jaggedben]

There have definitely been some threads on that section here, including relatively recently, although I can't readily point you to the best one. (Side gripe: It sucks that putting a code citation into the Search function on this forum usually gets you the error "The search could not be completed because the search keywords were too short, too long, or too common.")

You don't need NFPA membership to search past revision info. Just go here https://www.nfpa.org/codes-and-standards/7/0/70
Choose the past edition where the revision was made, and look at the relevant documents. Probably the 'Report on Proposals' or 'Report on Comments' for the time period you're interested in.

 

[rc/retired]

Dumb code. Maybe? I could be ok with the requirements in the basement. Crawl space, no way!

Ron

 

[WCEI]

There have definitely been some threads on that section here, including relatively recently, although I can't readily point you to the best one. (Side gripe: It sucks that putting a code citation into the Search function on this forum usually gets you the error "The search could not be completed because the search keywords were too short, too long, or too common.")

You don't need NFPA membership to search past revision info. Just go here https://www.nfpa.org/codes-and-standards/7/0/70
Choose the past edition where the revision was made, and look at the relevant documents. Probably the 'Report on Proposals' or 'Report on Comments' for the time period you're interested in.

The only substantiation that I could find in the ROP’s was that “smaller cables are more subject to damage than larger cable.”
I was hoping to see something better. Such as stating examples of damage that had created significant hazards.

I think this is a needless requirement that adds expense for no gain in safety.