How to run #6 wire across my basement joists?

[Allan Speers]

I'm planning to upgrade my garage shop's wiring, as I now have a 5 HP bandsaw, and hope to have a 3-5 HP DC soon. I have to run the main line about 125', fully across my basement. I imagine I'll use #6 wire and a 60a main breaker for the subpanel.

I've read that I can either drill holes in the joists, or use a "runner." I hate the idea of more holes in the joists, but I can't figure out exactly what a "runner" is. My neighbor, a general contractor, says you can use metal or pvc pipe, with the wire inside & the pipe stapled to the bottom of the joists.

Is this so? And it can be PVC? Aluminum? or just steel?

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Also, what about the (small) area where my wire will be running parallel with the joists?


- thanks.

[Jerry Bruette]

No expert here but I think the "runner" could be something like a couple 1X2's nailed to the bottom of the joists on each side of the cable to protect it, or maybe a 1X4 nailed to the joists and the cable stapled to the 1X4. I would staple the cable to the face of the joist where it runs parallel.

[Wade Lippman]

My code book is pretty old, but unless something has changed 334.15(c) allows running #6 stapled to the bottom of joists.

A running board is just a board nailed to the bottom of joists you can staple smaller wires to, to avoid drilling holes. Any cable can run along a joist.

Putting #6 through joist holes is painful. DAMHIKT

[Allan Speers]

I looked up the codes. I guess a "runner" is the same as a "running board," basically as Jerry described. Correct?

The requirements for the rest are a bit more complicated than I had read. (See below)

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quote: "Any cable can run along a joist."

Wade, do you mean "along a joist when running parallel to it" ? In that situation, (with NY State codes) I believe you are correct, though I don't understand what one is supposed to do in that scenario, each time the wiring comes to the occasional cross-joist. Do you just bend the wiring down, under the cross-joist, then back up again? That seems a little exposed to me.

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As for where the wiring is perpendicular to the joists, with less than 2X 6-gauge, or 3X 8-gauge, and you HAVE to use holes in the joist or a running board, (See below.)

I think the reasoning is that people might otherwise stupidly hang clothes & such on the wires.

Although I assume that 6-3 Romex means "3 X 6 gauge" and so can just be stapled to the bottom, I'm leaning towards steel conduit, just because it seems safer, and isn't horribly expensive, but I'm still hoping for more opinions.

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FWIW, here's the pertinent part of the NYS electrical code: (I'm pretty sure this is current and accurate, but best to check your own state.)


New York State CODE: ( NEC ) As of June 2015, NY State is using the 2011 NEC:


NM (non-metallic, sheathed) cable (such as Romex) used on a wall of an unfinished basement shall be permitted to be installed in a listed conduit or tubing.

• Where the cable is run at angles with joists in unfinished basements, cable assemblies containing two or more conductors of sizes 6 AWG and larger and assemblies containing three or more conductors of sizes 8 AWG and larger shall not require additional protection where attached directly to the bottom of the joists.

Smaller cables shall be run either through bored holes in joists or on running boards.
See section on RUNNING BOARDS, at the bottom of this page.
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HOLES & RUNNING WIRE:

Bored holes in HORIZONTAL framing members , such as joists, rafters, beams, etc shall be no less than 2 inches from the edge.

• Bored holes in studs and VERTICAL framing members for wiring shall be located 1.25 inches from the edge or shall be protected with a minimum 0.0625-inch steel plate or sleeve or other physical protection.

Holes can't be larger than 1/3 of the ACTUAL dimension of the lumber.
- This shouldn't be an issue as you should:
Limit the number of #14 or #12 cables in a hole to 4, for several reasons.

• Where run parallel with the framing member, the wiring shall be 1.25 inches from the edge of a framing member such as a joist, rafter or stud, or else shall be physically protected.

[Larry Frank]

It would be good to check your wire size. That is a long run and at 60 amps IMO you need a larger wire size.

[Julie Moriarty]

If you're concerned about meeting code, check with your local inspector. The NEC isn't universal. Municipalities make changes all the time.

If you're thinking about having to change things should you sell the house, local codes would probably prevail there too.

If you're thinking about what would be safe, you have to make sure the wires are protected. Idiot-proof protected. That runner idea may work but would it completely protect the wire from being damaged and exposing the conductors?

Personally, I'd run EMT conduit on the bottom of the joists and pull in the wire and you've satisfied pretty much every code or safety issue. If it's a straight run, you buy (2) 90s, pipe, a couple of connectors and some couplings and hangers. All you'll need is a hacksaw and something to ream the burrs out of the pipe. Use one-hole straps for hangers to keep the pipe tight to the bottom of the joist.

If you have a 1/4" rope, you can feed it in as you add pipe to the run or you can use a vacuum with a sandwich bag tied to a small line and suck that through the pipe. Then use the small line to pull in something strong enough for the wire pull.

If you have to make a small kick (bend) in the pipe, you can make those bends by fashioning some means to hold the pipe while you apply pressure to bend the pipe. I've used all kinds of building structures to make adjustments in a piece of pipe when a bender isn't handy. You just have to be careful not to bend so far that you kink the pipe. If you're careful, it can work just as well as a bender for small bends.

[David Kumm]

A benefit of conduit ( properly sized ) and THHN is that #6 is rated for more amps to give you more cushion. Dave

[Von Bickley]

Personally, I'd run EMT conduit on the bottom of the joists and pull in the wire and you've satisfied pretty much every code or safety issue. If it's a straight run, you buy (2) 90s, pipe, a couple of connectors and some couplings and hangers. All you'll need is a hacksaw and something to ream the burrs out of the pipe. Use one-hole straps for hangers to keep the pipe tight to the bottom of the joist.

That is the way I would do it.......

[Larry Frank]

When we did an remodel, the electrical contractor ran conduit across the basement ceiling and pulled wire in it. I think as others have mentioned that is the best way to go.

[Allan Speers]

Thanks, guys. As I wrote, I've been leaning towards conduit anyway, for the Safety factor.

Julie, those tips are GREAT ! - thanks.

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As for asking my local inspector - forget it. In Rockland County, NY they literally won't tell you what the codes are, even if you just want to check on work already done by a licensed electrician. - And all of the electricians I've talked to are also confused on many issues. Clearly, the county is purposely keeping things muddy so as to collect fines and pay-offs.

- but I digress.

FWIW, I WILL be having a licensed guy do the final main hookups & inspection.

[Allan Speers]

It would be good to check your wire size. That is a long run and at 60 amps IMO you need a larger wire size.

Does anyone agree with Larry?

Everything I've read says 125' of 6-3 Romex is adequate. Additionally, there is very little chance I'd ever be pulling 60a at once. I already bought the wire. Should I really consider heavier gauge?

[Stephen C Cunningham]

We have 6-3 on a 60a breaker feeding a sub panel for a new addition. Kitchen, familyroom and garage on two levels. Four major appliances, split a/c unit and a lot of halogen lights. Permits, inspected and passed. I think you have more than enough.

[Julie Moriarty]

Everything I've read says 125' of 6-3 Romex is adequate. Additionally, there is very little chance I'd ever be pulling 60a at once. I already bought the wire. Should I really consider heavier gauge?

When making long runs, we usually start looking at voltage drop when it gets into the 150' range. Since I've only worked with conduit in my career, I can't speak to voltage drop with romex. Insulation is a factor in calculating voltage drop and I have no idea what type of insulation your romex has. If you want to know for sure, Google "voltage drop calculator" and run the numbers. While you may never fully load the panel, it's best to do a proper installation.

[Von Bickley]

We have 6-3 on a 60a breaker feeding a sub panel for a new addition. Kitchen, familyroom and garage on two levels. Four major appliances, split a/c unit and a lot of halogen lights. Permits, inspected and passed. I think you have more than enough.

I agree with Stephen.....

[Allan Speers]

Thanks, all.


Julie: Are you saying that if one runs Romex inside a metal conduit (as I plan to do) this actually decreases any potential voltage drop?


I believe you, but that sounds like magic. What is the physics behind this?