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molo
07-24-2007, 07:15 PM
On securing wire inside walls... I have experimented with a cold wire and an open wall cavity. It seems that a stapled wire can't escape from a nail or screw, where a wire free in the wall cavity does. Why is it code to staple?

TIA,
Molo

jwelectric
07-24-2007, 07:59 PM
On securing wire inside walls... I have experimented with a cold wire and an open wall cavity. It seems that a stapled wire can't escape from a nail or screw, where a wire free in the wall cavity does. Why is it code to staple?

TIA,
Molo

334.30 Securing and Supporting.
Nonmetallic-sheathed cable shall be supported and secured by staples, cable ties, straps, hangers,

frenchie
07-24-2007, 08:28 PM
You wire shouldn't be fastened close enough to the surface to ever catch a nail or a screw. If it is, it should be covered with a nail guard.

Off the top of my head... if it isn't fastened, work on a connection at the box can jiggle the cable, inside the cavity. NM might rub against a nail, screw, or other sharp object. BX might come to rest against a copper pipe, and start corroding. Or, the cable could just get moved closer to the surface, where a nail might hit it later.

molo
07-24-2007, 10:01 PM
OK, Let me ask this, what ave. homeowner is going to know enough not to grab a 2 3/8" + screw and go to town hanging some heavy piece of art. Any screw over that length that wanders through the stud will penetrate a tightly secured non-metallic cable. This thread originates from a genuine concern about puncturin cable inside the wall cavity.

BrianJohn
07-25-2007, 04:52 AM
Fastening cable, prevents damage to the cable when hanging drywall this also simplifies hanging drywall as we know from expierence drywall hangers will cut any cables in their way.

jimbo
07-25-2007, 06:41 AM
Our walls are full of pipes and wires. Nail plates provide some protection as they pass through the studs. They do not protect cables and pipes which rise vertically between or next to studs. Careful and proper procedures will minimize damage, but nothing will ever completely prevent it.

Around here, it does not freeze, so water pipes are routinely placed in outide walls. I don't remember any project where the stucco people DIDN'T put a nail or screw through the sheathing into a copper pipe!

At home, due diligence on our part requires very careful testing before driving screws or nails. I start with a stud finder, but then always probe with a scratch awl to exactly find the edges of studs. If I can't drive a screw in straight, then I will have to accept the possible consequences.

CHH
07-25-2007, 07:03 AM
That reminds me of the DIY hanging a cabinet in the bathroom of a new home. He carefully located the stud and then drove the screw. The next moves were shutting off the water and calling a plumber since he had hit a water supply line to an upstairs bath.

The stud finder had indicated on the copper pipe and the guy was a careful enough worker that the screw was in the exact center of the tube. The guy did precise work, he just didn't know enough to realize that he had located a "stud" that wasn't a stud.

Missing a stud is easy enough. I worked on a framing crew one summer while in college so I try to think about where the studs should be and go from there. What tricks do other folks use?

jwelectric
07-25-2007, 07:46 AM
What tricks do other folks use?

what I do is


grab a 2 3/8" + screw and go to town hanging some heavy piece of art.

molo
07-25-2007, 11:32 AM
LOL JW, You'd be surprised, well...... maybe you wouldn't.

Mikey
08-04-2007, 06:06 PM
Molo, I've been asking the same question for years. I even ran some tests with nail guns and power screwdrivers to see what would happen, and in every case the unsecured cable moved out of the way of the fastener being driven, and the secured cable was damaged. Duh.

The approved methods of securing a cable when using steel studs leave the cable pretty loose, it seems to me, so there's nothing sacred about making it absolutely immobile.

Securing the cable also makes it a bitch to alter the installation after the walls are closed up.

However, there are provisions in the code relieving you of the requirement to secure a cable if the cable is fished, so that suggests a strategy...

hids2000
08-14-2007, 03:01 PM
is there a code for the distance between 2 cable staples? running the cable vertically on the side of a 2x4?
I know I have to put the first staple within 8 inches of a plastic box, or 12 inches of a metal box, but what about between the first staple and the top of the ceiling?

Assume the ceiling is 8ft in height.
The plastic outlet box is 12 inches off of the floor. staple #1 is 8 inches higher.
so when does staple #2, #3 and etc come into play?

jwelectric
08-14-2007, 03:03 PM
is there a code for the distance between 2 cable staples? running the cable vertically on the side of a 2x4?
I know I have to put the first staple within 8 inches of a plastic box, or 12 inches of a metal box, but what about between the first staple and the top of the ceiling?

Assume the ceiling is 8ft in height.
The plastic outlet box is 12 inches off of the floor. staple #1 is 8 inches higher.
so when does staple #2, #3 and etc come into play?


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 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.

hids2000
08-14-2007, 03:08 PM
great! just the info i need.
thanks.