NM cable across attic

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I have been reading this forum for quite a while. I need some advise for the best way to run and protect NM cable in an attic. Basically I have 5 (3-12/3 and 2-14/2) home-runs that go from an exterior panel to all the way across the attic. They are stapled to the roof rafters along a running board mounted about 24" high. I am worried that this location may be too hot and would like to move the cables lower. What is the best way to run and protect five cables running parallel for 50' in the attic? It will run next to a scuttle hole also.
 
I wouldn't worry about the heat. Moving the wires won't gain you anything. As far as the proximity to the scuttle hole, look at 320.23 (A).
 
NM wires are rated for 90 degrees Celsius which is 194 degrees fahrenheit, so the heat in the attic should not damage the wire. With an ambient temperature of 125 degrees fahrenheit the 90 degree ampacity would be derated to 76%. For a number 12 wire that would be 22.8 amps. Since the #12 NM can only be fused at a maximum of 20-amps, it is a non-issue.
 
Is a attic still a attic if there is no access at all to it once the home is sheetrocked? I guess I need a definition of a attic.
 
It would still be an attic just not an accessible one I guess. I am under the impression that building codes require access to attic spaces wether or not it will be used for storage.
 
2x4's will suffice as protection near the scuttle. You could always drill the ceiling joists, that eliminates the protection requirement...but that's a lot more work.
 
electricmanscott said:

I am under the impression that building codes require access to attic spaces wether or not it will be used for storage.
Click to expand...

I was too, but after I questioned a bldg inspector about it, I am not so sure. He said no, it does not have to be accessible. Now that may or may not be a local thing. :)
 
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