NM cable in unfinished basements

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powersystems

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Hi Guys,
The code article which is now 334.15(C) does not permit type nm cable smaller than # 8 to be secured to the underside of a joist. Does anyone know if this was the case in the 99 code?

TIA

Kevin
 
same basic rule in '99 at 336-6(c) for unfinished basements (not crawl spaces)
 
Without looking... I believe you could put "running boards" up to give additional physical protection and then you could run them on the underside of joists.

Quite honestly I don't see that all basements are equal and don't see the need for this rule to apply to all of them, but as written it does apply to all of them.
 
kwired said:
Without looking... I believe you could put "running boards" up to give additional physical protection and then you could run them on the underside of joists.

Quite honestly I don't see that all basements are equal and don't see the need for this rule to apply to all of them, but as written it does apply to all of them.
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I think you mean " or ON running boards" not beside running boards in 336.15(C) but then again I am looking at the 2011 edition. Section 334.23 refers you to Section 320.24 - "the cable shall be protected by substantial guard strips that are at least as high as the cable" but all that is in reference to attic spaces.

So with that said...sitting in an airport I don't have access to the 1999 NEC but chances are the verbiage is the same.
 
In attic where potential for stepping (step potential?) Is greater, protection is provided by something higher to step on.
Below ceiling, support and protection from getting hooked is provided by being attached to the surface of a board.

Tapatalk!
 
This is just a very stupid rule...it is much easier to use the NM as a hanger rod when it is run through holes in the joists than when it is installed on the bottom of the joists. When on the bottom it is only supported every 48" and sags too much to be a good hanger rod...the holes in the joists provide support every 16" and the NM does not sag near as much when used as a hanger rod.:D
 
don_resqcapt19 said:
This is just a very stupid rule...it is much easier to use the NM as a hanger rod when it is run through holes in the joists than when it is installed on the bottom of the joists. When on the bottom it is only supported every 48" and sags too much to be a good hanger rod...the holes in the joists provide support every 16" and the NM does not sag near as much when used as a hanger rod.:D
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:lol::lol::lol::lol:
 
don_resqcapt19 said:
This is just a very stupid rule...
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And it got stupider in '08 when they made the same rules apply to crawl spaces.

it is much easier to use the NM as a hanger rod when it is run through holes in the joists than when it is installed on the bottom of the joists. When on the bottom it is only supported every 48" and sags too much to be a good hanger rod...the holes in the joists provide support every 16" and the NM does not sag near as much when used as a hanger rod.:D
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Good reason to not wire with anything smaller than 10AWG NM.
 
The oldest code I have handy is the 1978 code and the rule is essentially the same except it was section 336-8.
 
GoldDigger said:
Below ceiling, support and protection from getting hooked is provided by being attached to the surface of a board.
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Do not underestimate the abilities of dwelling occupants, if it is even slightly visible - it may end up having something hanging from it.

don_resqcapt19 said:
This is just a very stupid rule...it is much easier to use the NM as a hanger rod when it is run through holes in the joists than when it is installed on the bottom of the joists. When on the bottom it is only supported every 48" and sags too much to be a good hanger rod...the holes in the joists provide support every 16" and the NM does not sag near as much when used as a hanger rod.:D
Click to expand...
You smile at the end of that, but what you say is very logical and has a lot of truth to it.

Also consider that if you run raceway wiring methods, that only increases the amount of weight that may end up being hung from the wiring by building occupant.
 
kwired said:
Do not underestimate the abilities of dwelling occupants, if it is even slightly visible - it may end up having something hanging from it.

You smile at the end of that, but what you say is very logical and has a lot of truth to it.

Also consider that if you run raceway wiring methods, that only increases the amount of weight that may end up being hung from the wiring by building occupant.
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I propose some sort of break away staple or maybe when NM is run perpendicular on the face of the joist we should install an alternative hanging bracket per so many feet run:D.
 
I propose we stop worrying about it. :cool:


Having seen lots of stuff hanging from NM in basements and never seeing actual damage caused by it I think it is a non-issue.

Sure, no doubt someone has seen damage from this but I we have also seen NM damaged inside walls. The frequency of damage does not seem to justify the amount of hand wringing that goes on over this subject. :)
 
iwire said:
I propose we stop worrying about it. :cool:


Having seen lots of stuff hanging from NM in basements and never seeing actual damage caused by it I think it is a non-issue.

Sure, no doubt someone has seen damage from this but I we have also seen NM damaged inside walls. The frequency of damage does not seem to justify the amount of hand wringing that goes on over this subject. :)
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I agree with that.

Besides the AFCI's are supposed to protect us from anything happening in those cases:roll:
 
don_resqcapt19 said:
This is just a very stupid rule...it is much easier to use the NM as a hanger rod when it is run through holes in the joists than when it is installed on the bottom of the joists. When on the bottom it is only supported every 48" and sags too much to be a good hanger rod...the holes in the joists provide support every 16" and the NM does not sag near as much when used as a hanger rod.:D
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I am egar to await your 2017 PI proposal :)
 
Back when I was a pup the fellow that taught me some Code states the reason was that homeowners were prone to nail/screw cover (back then "beaver board" was popular) directly to the bottom of floor joists. The smaller Romex would conform to the soft board leaving a relatively smooth surface... until the NM was hit by a nail or screw :)
I have no information to verify his statement.. old wives tale or true ..who knows..
 
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