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#198482 - 01/23/11 07:59 PM The 1-1/2" Thick "2x4"
renosteinke Offline
Cat Servant
Member

Registered: 01/22/05
Posts: 5299
Loc: Blue Collar Country
I was watching one of those HGTV shows, where they were covering a brick wall with drywall.

The drywall was framed off the brick with 2x4's, laid 'sideways.' The wiring method was NM (Romex).

Think about that for a second. I saw two challenges to this wall.

The first is that code required the cable to be 1-1/4" behind the wall face, or to be covered by some stout metal. Even mounting the cable to the bricks you're hard pressed to maintain that spacing.

Challenge #2 was getting the cable into the boxes. Heck, getting the boxes into the bricks is a challenge itself - but where is there room for your wire to enter?

How would you do this job? Would you insist on a deeper wall cavity?

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#198484 - 01/23/11 08:19 PM Re: The 1-1/2" Thick "2x4" [Re: renosteinke]
George Little Offline
Member

Registered: 01/18/04
Posts: 1492
Loc: Michigan USA
Reno- the wording say that the NM cable needs to be 1-1/4" away from the nearest edge of the framing (furring in this case) member so move it away and secure the cable to the masonry wall, then enter into the side of the box.


NEC 300.4(D) '08 Edition.
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#198485 - 01/23/11 08:27 PM Re: The 1-1/2" Thick "2x4" [Re: George Little]
gfretwell Offline

Member

Registered: 07/20/04
Posts: 9012
Loc: Estero,Fl,usa
I know that is the current reading but I am old enough to remember when it was the depth from the face of the framing to the wire, no matter how far it was away. I think the invention of the "stacker" prompted the changing of the reading.
If you look at a house built in Florida before the 90s you will see EMT coming down a masonry wall when it is furred and dry walled. I always thought that was the right way to do it.
If you don't agree, think about that homeowner hanging a picture while he is barefoot on that terrazzo floor.
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#198487 - 01/23/11 08:57 PM Re: The 1-1/2" Thick "2x4" [Re: gfretwell]
PAteenlectrician Offline
Member

Registered: 01/06/11
Posts: 69
Loc: Cressona, Pa, U.S.A. (Schuylki...
If you put a scerew through emt, You're grounded. grin


Edited for spellin


Edited by PAteenlectrician (01/23/11 08:59 PM)

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#198488 - 01/23/11 08:59 PM Re: The 1-1/2" Thick "2x4" [Re: PAteenlectrician]
George Little Offline
Member

Registered: 01/18/04
Posts: 1492
Loc: Michigan USA
Greg, the one that gets me is the contractor will run NM cable in FMC along the side of the furring strip and say it's protected.
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#198489 - 01/23/11 09:27 PM Re: The 1-1/2" Thick "2x4" [Re: George Little]
gfretwell Offline

Member

Registered: 07/20/04
Posts: 9012
Loc: Estero,Fl,usa
They did say EMT and it was in a connector on the metal box end so PA would be grounded (as in operate the O/C device).
The usual method was a 10' stick, bent into a 90 at the top of the framing into the attic a way and they shoved the RX down that pipe. One thing that really made it nice for me was I was able to belly far enough into the low part of a 3:12 attic to slip on another EMT and tighten the connector. Then I could yank out the existing 14-2, set a J box where I could get to it, pull in THHN and add a circuit.
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#198490 - 01/23/11 09:29 PM Re: The 1-1/2" Thick "2x4" [Re: George Little]
Niko Offline
Member

Registered: 08/17/06
Posts: 358
Loc: Campbell, CA
Install 4s metal box with side KO with 1/2" or 1/4" mud ring.
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#198494 - 01/23/11 09:50 PM Re: The 1-1/2" Thick "2x4" [Re: Niko]
sparkyinak Offline
Member

Registered: 07/08/07
Posts: 1286
Loc: Alaska
1/2" EMT into a 4 square and mud ring. Need more volume? 4-11/16" box with mud ring. How ever a 4 square should be sufficient. Prior planning prevents piss poor performance. laugh

Hey, maybe I'll update my signature quote with that


Edited by sparkyinak (01/23/11 09:52 PM)
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#198503 - 01/24/11 09:38 AM Re: The 1-1/2" Thick "2x4" [Re: renosteinke]
renosteinke Offline
Cat Servant
Member

Registered: 01/22/05
Posts: 5299
Loc: Blue Collar Country
You're all on the same page as I am ...

If you staple the Romex to the firring strip, you're in violation. If you attach it to the wall, you're barely legal - until you get to the box, where you have to get closer to the wall to enter the KO/fitting.

Conclusion: You either need a deeper wall, or a different wiring method. I don't think -please correct me - that MC has the depth requirement.

Now, there's nothing preventing the remodeler from using much slimmer firring strips - either 1x's or 'hat channels' attached directly to the bricks. In that case, you're really SOL, completely unable to legally run your wires or set your boxes. Hello Wiremold frown

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#198504 - 01/24/11 10:27 AM Re: The 1-1/2" Thick "2x4" [Re: renosteinke]
gfretwell Offline

Member

Registered: 07/20/04
Posts: 9012
Loc: Estero,Fl,usa
The 1x is the common method in old Florida houses (no insulation) and that is what prompted the EMT rule in the first place.
The AHJs just have a wink and smile attitude about the last couple inches of wire that enters the box, less than 1.25" from the furring
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