Properly mounted box?

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JohnJ0906

JohnJ0906

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Baltimore, MD
I didn't want to hijack this thread, but I did want to ask - is mounting a nailon box this way a violation or not?

toh.jpg


I was taught that it was a violation to secure a box like this with screws straight through the back, unless the plastic was formed with screw holes.
 
I believe it is a violation although I have seen it done many times. My understanding is that the screws would need to have a place to recess so that they cannot be energized. Also the box probably has not been tested for that install. Big deal right.
 
The OP is referring to nonmetallic boxes and 314.43 do not allow drilling and mounting the boxes without the box being constructed so as to prevent contact between the conductors in the box and the supporting screws. The device box in the photo is not so constructed, at least none that I have see but, new products appear everyday.
 
Dennis Alwon said:
I believe it is a violation although I have seen it done many times. My understanding is that the screws would need to have a place to recess so that they cannot be energized. Also the box probably has not been tested for that install. Big deal right.
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Yep. This is one violation I would not get to worried/excited about.:smile:
 
Mvillines said:
The OP is referring to nonmetallic boxes and 314.43 do not allow drilling and mounting the boxes without the box being constructed so as to prevent contact between the conductors in the box and the supporting screws. The device box in the photo is not so constructed, at least none that I have see but, new products appear everyday.
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Not so split hairs but do Construction Specifications and field drilling have the same requirements? I'm not disagreeing with you just trying to clear this in my head. ;)

III. Construction Specifications
314.43 Nonmetallic Boxes.
Provisions for supports or other mounting means for nonmetallic boxes shall be outside of the box, or the box shall be constructed so as to prevent contact between the conductors in the box and the supporting screws.
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another log on the fire

another log on the fire

Lets throw in 334.30 while we are at it.

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
(41⁄2 ft) and within 300 mm (12 in.) of every outlet box

I see no finished walls that need to be fished, Strap anyone?
no excuse ,

(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
 
Subject to damage lets just use a little common sense Yes we all drill holes where we need them and there not but for cripes sake this is crazy!!!:D
 
Depending on the use of the box, such as for receptacles or switches can make a difference.

When screwing through the wall of the box, and the receptacle may be plugged into many times over the life of the install, how can we be sure the wall will not crack or the screw finally work its way through the plastic? We don't and it has not been tested that way [110.3(B)], hence it is not a permitted method of installation.

There are boxes that have been designed for just such an installation, so it would not be a hardship to install one.

That is what planning is for. :wink:
 
how can we be sure the wall will not crack or the screw finally work its way through the plastic?
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How can we be sure we won't get hit by a bus? We look both ways before crossing the street.

Your logic is dumb. You are suggesting that they engineered the box only to be nailed on to a stud, they somewow used difeerent plastic to hold the nails in place? Common sense tells me that they engineered the box for capacity, size, ease of installation and fire rating. If there is a weak point on the plastic, it would be the nail holders, not the back of the box.

We are allowed to use our giant human brains and make some decisions in the field. Otherwise, nothing would ever get done. You can't write every single detail into instructions. The installation is fine. The screws are within 1/4" of the back of the box. Obsessive compulsion wastes resources.
 
220/221 said:
How can we be sure we won't get hit by a bus? We look both ways before crossing the street.

Your logic is dumb. You are suggesting that they engineered the box only to be nailed on to a stud, they somewow used difeerent plastic to hold the nails in place? Common sense tells me that they engineered the box for capacity, size, ease of installation and fire rating. If there is a weak point on the plastic, it would be the nail holders, not the back of the box.

We are allowed to use our giant human brains and make some decisions in the field. Otherwise, nothing would ever get done. You can't write every single detail into instructions. The installation is fine. The screws are within 1/4" of the back of the box. Obsessive compulsion wastes resources.
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"your logic is dumb"

I generally have conversations with children who have better sense than to say one's opinion, being different, is not dumb, just a different angle.
I am sorry you do not like my opinion, but that is what this site is all about.

As for dumb, since we do not have an answer from the manufacturer, we have no idea how they have designed their boxes.
My past experience, which is more than 25 years with plastic boxes, has proven to me that these boxes do fail, even at the fastening points. I am not suggesting at all that they use different plastic for different parts of the box, that is your emotional reaction to my comments.
What I will go on record as saying, is that the thickness of the plastic at the fastening portions of the boxes may be thicker than the walls of the boxes.

Therefore as the inspector, I would be inclined to say that the box has not been designed for this method of installation.
If I were to receive a letter from the manufacturer showing me otherwise, I would gladly concede that it is fine for installation.

In our industry, we/I try not to leave an installation up to guessing whether or not the install will be safe, that is how/why the NRTLs were developed...someone (through engineering) tests for the proper method of installation/suitability of installation.
As I mentioned, there are boxes suitable for the means, so it is not a hardship.

Of course this is all just my humble opinion. ;):cool:
 
So let me get to the point of the OP... Technically, a 4" x 4" x1.5" (1900 box) with a mud ring would be the correct installation.

$0.33 for a blue box.

about $4.50 for labor cost.

Correct box...

$1.29 for 4' x4' x 1.5" box

$0.59 for a 1/2" plaster ring

$0.13 for a platic romex connector

about $9.00 for labor cost.


So is it about cost - $4.88 vs approx. $11.01;

or, not having the knowledge to upsell the correct item to insure that it will pass inspection first time, everytime?
 
If a crew member was going to do this, would they most likely use panheads with fender washers to reduce risk to plastic? Throw some tape on the pan/washer to avoid shorting poential?
 
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