Protecting plastic nail on boxes.

[chicar]

I had an Inspector tell my forman he had to install metal plates on the back side of plastic nail on boxes because the back pertrudes the 1 1?/4 allowance of the 2x4 studs. I told the AHJ is nuts and I would get the Forum's opion.

 

[iwire]

Re: Protecting plastic nail on boxes.

300.4(D) and the other sections that ask for nail plates only specify cable or raceways, not boxes.

 

[bphgravity]

Re: Protecting plastic nail on boxes.

There is nothing in the code that requires protection of plastic boxes from damage or in this protecton from nail or screw penetration.

I feel that in some cases, an AHJ must evaluate the types of materials used to ensure it meets conditions of use, but this is way overboard.

 

[hbiss]

Re: Protecting plastic nail on boxes.

Nothing in the code but he does have a point. If we are going to be so fussy about the 1-1/4" rule then it makes sense to extend it to plastic boxes as well as cables in the center of the bay. If someone is going to put a long screw or nail in the wall what makes you think its always going to be right on either side of a stud?

-Hal

 

[chicar]

Re: Protecting plastic nail on boxes.

Our cable have to be located in the center of the studes. If more than one wire is used than we use a caddy wire stacker thingee or a Colorado jim thingee.

 

[jimwalker]

Re: Protecting plastic nail on boxes.

I do see his point but have only seen it as a problem a few times.At least it is easy to fix .Maybe they need to add this to boxes

 

[bphgravity]

Re: Protecting plastic nail on boxes.

I've seen more damage to conductors due to the staples securing the cable than I have from nails or screws. If a person takes care when penetrating a wall, they should be able to avoid a box. Its a simple matter of looking on the other side of the wall to see what is there. And though it is fairly easy to screw a drywall screw into a plastic box, it does resist the drive of a nail fairly decently.

 

[electricmanscott]

Re: Protecting plastic nail on boxes.

Cuckoo...Cuckoo...Cuckoo! :roll:

 

[roger]

Re: Protecting plastic nail on boxes.

Scott, I love your way with words.

Roger

 

[charlie]

Re: Protecting plastic nail on boxes.

Scott, that is the way I felt when the proposal was made to protect horizontal runs between the furring strips in a basement where insulating board was grooved for cable. I was surprised when the panel accepted the proposal. I would be surprised now if the panel didn't accept a proposal to require nail guards behind non-metallic boxes.

 

[hbiss]

Re: Protecting plastic nail on boxes.

Its a simple matter of looking on the other side of the wall to see what is there.
Easy enough for us to say but what about the brain dead homeowner who hasn't a clue about what's in the wall or how it's constructed.

Looks like the 1-1/4" rule is there to minimize damage to cables caused by drywallers missing the studs but didn't this all come about because a HO was electrocuted hanging a picture or is that just a myth?

-Hal

 

[russellroberts]

Re: Protecting plastic nail on boxes.

If that's the case,why not just disallow plastic/fiber boxes altogether,and go back to metal boxes?

It still wouldn't matter in my way of thinking,because most boxes have the wire entry holes for romex right in the back. Way closer than 1 1/4 from the edge of the stud.

Russell

 

[a.wayne3@verizon.net]

Re: Protecting plastic nail on boxes.

I`ve thought of this same thing time and time again.When the AHJ looked at a stud and said 1 1/4 rule i looked at the box and thought what about the wires entering the box ???As far as I am concerned the 1 1/4 rule was designed for offset holes in studs and drwall fasteners.you can notch a piece of lumber and use a nail plate to cover it but going in a circle the wire is still within 1 1/4 of the stud/furring.read my post 300.4 D overkill that took this article to the extreme and almost caused a fatal event.

 

[hurk27]

Re: Protecting plastic nail on boxes.

Hey we have siders up here that will drive a 2" roofing nail through the back of a service!
Then ask what was that loud bang when they hit the main buss

 

[goldstar]

Re: Protecting plastic nail on boxes.

Hey we have siders up here that will drive a 2" roofing nail through the back of a service!

I've been waiting for this to happen here in my area but haven't seen it yet. I've seen them nail through the back of the cabinet and miss the buss bar by 1/4" and even drop old siding and break the glass on the meter. I guess it's only a matter of time.

Anyway, back to the original question (good point or not), you're right - the AHJ is nuts but our opinions here are just that - opinions. If the CMP wants to make a change in the future and require PVC box mfrs. to make their boxes with rear metal plates then so be it. But as of right now, as far as I know, PVC boxes are approved for their use. (And, by the way, if we install a metal plate are we required to bond it with the EGC ?)

If we start making changes to our installation techniques so that the main intent of our installations switches from "neat and workmanlike" to "preventive and cautionary" we might as well pack up and open a 7-11 because we might all go broke doing this. Should tin knockers install shrouds so that their duct work isn't perforated ? Or plumbers for their pipes ? Why don't we just go back in time and require a/c cable and metal boxes instead of nmc and pvc boxes ??? That way we can be sure to satisfy everyone but especially that occasional AHJ who wants to over-enforce what he thinks the code should be.

I'm a proponent of requiring that all trades be licensed. That way if a sheet-rocker misses a stud and drives a nail through our wiring, he/she bears the onus of responsibility and not us because our wire extends beyond the 1 1?/4" rule at the entry point of the box. What I'd really like to see happen is a ban on sheet-rockers using roto-zips to cut out for electrical boxes. That way they won't rip up our wires inside the boxes.

Sorry. Just my opinion. Didn't mean to get up on the box !!!

 

[wirebender]

Re: Protecting plastic nail on boxes.

What I'd really like to see happen is a ban on sheet-rockers using roto-zips

Where do I sign the petition?

 

[jimwalker]

Re: Protecting plastic nail on boxes.

They tear up my wires i bill them.And i was told by an inspector that routers are actually illegal but good luck inforcing it.A surprising thing is many counties and states have permitted romex to be stapled right next to that firing strip and very few problems from it.

 

[iwire]

Re: Protecting plastic nail on boxes.

Originally posted by jimwalker:
i was told by an inspector that routers are actually illegal but good luck inforcing it.

Jim did he look like he came from the bar before he told you this.

Personally I like the Rotozips as long as the operator knows (or cares

 

[jimwalker]

Re: Protecting plastic nail on boxes.

Our inspectors would never drink
was told this too many years ago to even remember witch inspector told me this and i agree if they use them properly they make fine holes.The problem is drywall hangers try to go too fast.Only way to break them from hitting our wires is a backcharge.

 

[a.wayne3@verizon.net]

Re: Protecting plastic nail on boxes.

Jim piece work drywallers set the roto zip at the max depth.That1s why i have the guys roll all wires into a circle rather than bend them neat and pretty.I have been in fla.working since 1982 have never heard of that violation.Routers are illegal !!!BTW I do remember wiring homes and stapling to the furring sides try that now LOL LOL LOL