romex and floor joist

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domnic

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Electrical Contractor
At what height can I staple nm ( romex ) to the bottom of floor joist in a basement of house rather than bore holes?
 
You will need to use running boards for all nm cables smaller than size #6 if you run across the bottom edge of the floor joists. No height specified, your AHJ may be able to give you one though.
 
Depends also what code cycle you are under. The 2011 , I believe, changed it to running boards or boring holes even in crawl spaces as Mikey stated. If it is a basement I suspect you need the running boards or bore holes. We would square off the nm cable and run it close to the outer walls. Some we would be able to nail to the plate atop of the block wall while the others could be boxed in
 
I can't see where the NEC ever allows it in an "unfinished basement or crawl space" (as far as Romex smaller than #8).
Local jurisdiction may, of course, amend that
 
augie47 said:
I can't see where the NEC ever allows it in an "unfinished basement or crawl space" (as far as Romex smaller than #8).
Local jurisdiction may, of course, amend that
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Gus 334.15(C)

(C) In Unfinished Basements and Crawl Spaces. Where
cable is run at angles with joists in unfinished basements
and crawl spaces, it shall be permissible to secure cables
not smaller than two 6 AWG or three 8 AWG conductors
directly to the lower edges of the joists. Smaller cables
shall be run either through bored holes in joists or on running
boards. Nonmetallic-sheathed cable installed on the
wall of an unfinished basement shall be permitted to be
installed in a listed conduit or tubing or shall be protected
in accordance with 300.4.
Click to expand...
 
augie47 said:
I thought we were saying the same thing :)
OP asked at what height.. I meant to answer "can't regardless of height"if its a crawl or unfinished basement...
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Gotcha-- I thought you were saying that the nec didn't allow smaller than 6 thru bored holes. I should have known better...:D
 
augie47 said:
I can't see where the NEC ever allows it in an "unfinished basement or crawl space" (as far as Romex smaller than #8).
Local jurisdiction may, of course, amend that
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Prior to the 08 NEC, it was allowed in crawl spaces. and we (VA) are one of those local jurisdictions that still allow NM run perpendicular in crawl spaces (amendment to 2012 IRC).

electrofelon said:
I would go ahead and drill holes. Besides stapling perpendicular to the joists being a super mongrel installation, i find it much faster to drill rather than staple.
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Yes! Boring holes is easier/faster than driving staples overhead or on my back. Plus you can bore any size hole for extra cables.
 
over head romex height for stapled to Joist bottom

over head romex height for stapled to Joist bottom

I know I got shot down on this before …

But I just can't get over it .

In the Old Days I picked up a bad code ref .

NM could be stapled to the bottom of a floor joist if , 8 feet ABFF



Well . Any one else ever play that game ?

DOMINIC - I know about the , # 8 wag , I thought that there was height a long time ago , actually tight that ...


Don
 
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Read up on "Boring & Notching" in your building code so you don't end up in a bad situation.
Every building code has very basic guidelines to follow, usually saying no notching in the center 1/3 of a span, bored holes greater than x diameter shall be n distance from an edge, etc...
 
iwire said:
We are all so set in our ways, I think running boards are faster than drilling and threading cables. :)
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Yes, and some of us are faster at running raceway then installing running boards plus stapling cables to them.;) Usually looks neater as well.
 
iwire said:
We are all so set in our ways, I think running boards are faster than drilling and threading cables. :)
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The OP doesn't say what we are dealing with here, all he says is basement.

You may have floor joist on 12" centers or trusses at 24". You may have nice new wood or some so old it's petrified. How many cables is he running 2 or 20? He doesn't say how far the cable will run, 10 ft or 50 ft. He doesn't say if they can all run in the same location. There are a lot of factors to consider.

I would normally drill holes in a basement because they may wish to finish the space one day but in a crawl space I would do whatever was the least amount of work.
 
Dennis Alwon said:
We would square off the nm cable and run it close to the outer walls. Some we would be able to nail to the plate atop of the block wall while the others could be boxed in
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Dennis I'm glad that some people do think ahead and not just get the job done as fast as possible and get the heck out of there.
 
JFletcher said:
Yes! Boring holes is easier/faster than driving staples overhead or on my back. Plus you can bore any size hole for extra cables.
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That all depends on how many holes and cables we're talking about. Pulling multiple cables through a long run of holes is no picnic, especially if you get that NM cable that has the consistency of fine sandpaper.
 
peter d said:
That all depends on how many holes and cables we're talking about. Pulling multiple cables through a long run of holes is no picnic, especially if you get that NM cable that has the consistency of fine sandpaper.
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C'mon, didn't you read the '' mactip of the day! '' about using wire lube on romex while pulling thru holes in floor joist?
 
growler said:
I would normally drill holes in a basement because they may wish to finish the space one day but in a crawl space I would do whatever was the least amount of work.
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Where I live the joists would get strapping ahead of drywall so no need to bore holes for small cables.
 
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