Cabling and Conduit in Attic

[jkd]

I was going to DIY some new electrical and network runs in my home. Using romex and cat-6 cabling, they would be running up the walls and traverse across the attic, which is filled with that loose blow-in insulation stuff. My question is: does the romex and cat-6 ethernet cables need to be run in conduit up in the attic? Or do people just run the cables bare and let them lay in the loose insulation?

 

[ycgoat]

Your local jurisdiction may require conduit

 

[mike93lx]

I wouldn't lay it loose across the attic. I needs to be secured

 

[Innovate1]

I think most places just require some sort of protection such as a board run along with the wire. This protects it from people walking around on the trusses and such like. I have also run it on the bottom of the top cord near the sides where the clearance is low so minimal chance of something damaging it without a runner board without any inspection issues.

 

[jkd]

Is the primary concern for people stepping on the cables and potentially damaging them? Or is it more for critters chewing on the cables? Or both?

 

[nadogail]

I like to have some physical support for cables, sometimes I use "Running Boards" made from 1" lumber to fasten the cables to.

 

[FredWanaker]

depends on codes where you are, but romex can be run from truss to truss in many places. When doing so it still needs to be secured every X number of inches. The key is what kind of attic. If it one with stairs, where people go up in it, store things etc., then it has to be better protected than in an attic where people never go. It should never be in a place where people are climbing over it, stepping over it, to get around.

 

[wssix99]

For the CAT-6, I would go with plenum rated cable. (but you could probably do another type if you don't want to pay for plenum) https://sewelldirect.com/blogs/learning-center/understanding-plenum-and-other-nec-cable-ratings

 

[FredWanaker]

City code told me that plenum cable is only needed here in residential if you run it inside the plenum.

 

[wssix99]

City code told me that plenum cable is only needed here in residential if you run it inside the plenum.

I have a strong aversion to fire, so I'd lean towards plenum cable anyway. But, our house was struck by lightning... and some of the bolt found ground through a sensor we had on the roof, which was connected through our CAT6 system:

I'm not sure if the plenum cable made a difference under the heat of 300 million volts, but I'm really happy I was using it!

 

[ycgoat]

I think plenum is a low smoke insulation to help reduce the toxic fumes during a fire

 

[alfredeneuman]

I looked up "attic" in the NEC. The individual articles referenced this:

(A) Cables Run Across the Top of Floor Joists. Where run across the top of floor joists, or within 2.1 m (7 ft) of the floor
or floor joists across the face of rafters or studding, the cable shall be protected by guard strips that are at least as high as the cable. Where this space is not accessible by permanent stairs or ladders, protection shall only be required within 1.8 m (6 ft) of the nearest edge of the scuttle hole or attic entrance.

(B) Cable Installed Parallel to Framing Members. Where the cable is installed parallel to the sides of rafters, studs, or ceiling
or floor joists, neither guard strips nor running boards shall be required

 

[Innovate1]

Is the primary concern for people stepping on the cables and potentially damaging them? Or is it more for critters chewing on the cables? Or both?

Not for critter protection. Hopefully you keep those out of the building. It's for stepping on them, laying heavy stuff on them, whacking them with long lumber (in the case of wiring across open stud cavities in a garage used as a wood shop for example) and such like. At least that's the way I understand it and that makes sense to me.

 

[wyliesdiesels]

For the CAT-6, I would go with plenum rated cable. (but you could probably do another type if you don't want to pay for plenum) https://sewelldirect.com/blogs/learning-center/understanding-plenum-and-other-nec-cable-ratings

plenum is overkill in a residence... but by all means if you want to waste the money and lighten your wallet