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I am fresh out of cable staples and would rather not go all the way to Lowe's just to get a box. What are the implications of not fastening loose electrical wires to a stud? It's not like there's going to be that much vibration in my house.

Edit: This is what I am talking about.

wire clip

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3
  • You could also use armored cable, known as BX in some quarters.
    – Phil N
    Nov 11, 2015 at 0:28
  • In the UK where the answer would be: No, you don't have to secure interior electrical wire to anything.
    – AndyT
    Nov 11, 2015 at 14:18
  • The vinyl sheathing on NM cables will burn. When the flame hits one of these staples, the flame will typically go out.
    – Craig Tullis
    Sep 15, 2016 at 21:17

5 Answers 5

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If you continue reading NEC 334.30 you'll come to subsection (B)...

334.30 Securing and Supporting Nonmetallic-sheathed cable shall be supported and secured by staples, cable ties, straps, hangers, or similar fittings designed and installed so as not to damage the cable, at intervals not exceeding 1.4 m (4 1⁄2 ft) and within 300 mm (12 in.) of every outlet box. junction box, cabinet, or fitting. Flat cables shall not be stapled on edge. Sections of cable protected from physical damage by raceway shall not be required to be secured within the raceway.

(A) Horizontal Runs Through Holes and Notches. In other than vertical runs, cables installed in accordance with 300.4 shall be considered to be supported and secured where such support does not exceed 1.4-m (4 1⁄2-ft) intervals and the nonmetallic-sheathed cable is securely fastened in place by an approved means within 300 mm (12 in.) of each box, cabinet, conduit body, or other nonmetallicsheathed cable termination.

FPN: See 314.17(C) for support where nonmetallic boxes are used

(B) Unsupported Cables. Nonmetallic-sheathed cable shall be permitted to be unsupported where the cable:

(1) Is fished between access points through concealed spaces in finished buildings or structures and supporting is impracticable.

(2) Is not more than 1.4 m (4 1 ⁄2 ft) from the last point of cable support to the point of connection to a luminaire or other piece of electrical equipment and the cable and point of connection are within an accessible ceiling

So if the structure is accessible, you must secure the cable. If you are fishing cable, you do not have to secure the cable. No trained mice with staplers required.

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  • +1 but, doesn't this cause a danger of hitting the wire when nailing/drilling into the walling?
    – BlueRaja - Danny Pflughoeft
    Aug 21, 2013 at 19:09
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    @BlueRaja-DannyPflughoeft This is why you make sure you know what's in a wall, before you start nailing/drilling.
    – Tester101
    Aug 21, 2013 at 20:30
  • That is of course an insane request to make. Unless I was there when the house was built, I have no idea what's behind the walls. But I'd assume that I can nail a poster to the wall without killing myself.
    – BlueRaja - Danny Pflughoeft
    Aug 21, 2013 at 23:10
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    @BlueRaja-DannyPflughoeft Unless you're using a high speed nail gun, the cable should have enough slack to move out of the way when you hang your poster. If you're cutting open the wall or doing anything else that is likely to damage the cable, you've probably already used a stud finder to locate the framing members. Most modern stud finders include a feature for finding electrical lines, so you'll probably already have a good idea that they're there.
    – Tester101
    Aug 22, 2013 at 11:56
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    @BlueRaja-DannyPflughoeft I also offer a money back guarantee on all my answers. So if you kill yourself hanging a poster because of this answer, I'll refund what you paid for the answer ;)
    – Tester101
    Aug 22, 2013 at 11:59
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Yes. It will not pass code without them.

NEC 334.30 and 314.17 Type NM (nonmetallic) cable shall be secured at intervals not exceeding 4.5 feet and within 12 inches of each box. When a single gang box 2-1/4” x 4” or smaller is used without a cable clamp, the cable shall be secured within 8” measured along the sheath.

Staples

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  • 12
    what if you are fishing wire through a wall?
    – Steven
    Jan 22, 2012 at 3:02
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    @Steven - I've never heard of an inspector calling that. I guess electricians will have to start training mice to staple wire if the inspectors start calling it;)
    – lqlarry
    Jan 22, 2012 at 3:33
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    @Steven see subsection (B)Unsupported Cables.(1) of NEC section 334.30.
    – Tester101
    Jan 22, 2012 at 18:24
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    @Steven, part of the reason for fixing the cable is so it does not get damaged when the plaster board is fixed to the wall, or over the many weeks between "first fix" and finishing the all.
    – Walker
    Jan 22, 2012 at 21:33
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    I get annoyed at "because it's code" answers. What is the hazard? I'm not convinced that a free floating cable in a non-insulated cavity is in more danger from a drill or nail than one that is pinned to a stud.
    – Sherwood Botsford
    Jul 13, 2019 at 23:16
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The biggest problem could be if the cable moves away from the stud and you drill into the wall and nick the cable...

Depending on where you are based there could be building code/regulation violations involved as well.

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  • 3
    It seems like the cable would be even more susceptible to piercing by a screw or nail if it's fastened tight and unable to move.
    – oscilatingcretin
    Jan 22, 2012 at 0:31
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    @oscilatingcretin - if it's fastened you know where it is so you can avoid it. If it's not fastened it could be anywhere.
    – ChrisF ♦
    Jan 22, 2012 at 20:39
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    The answer is clear: Knob & Tube wiring. The conductors are separate :-)
    – Bryce
    Jun 19, 2012 at 2:33
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    If the cable is secured to the stud then a drill or nail that just misses the stud has a supported target.
    – Sherwood Botsford
    Jul 13, 2019 at 23:17
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Better safe than sorry. Unforeseen actions may occur within a wall cavity at later dates, and though it is highly unlikely that any action would occur to move or damage the cable, storm activity or remodeling may do such. Staples are cheap. Unless is it impossible to reach, secure the cable as per NEC requirements. Tidy work is quality work.

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1

If a wire is fastened along a stud’s center it insures that any nail or screw through 1/2” drywall would need to be at minimum 2” long to reach the wire. Standard drywall screws are only 1 1/4”.

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