Securing Romex to block wall with 1" Rigid Foam board and 1/2" fur strips on top of foam board

I always use a 5/8" raised plaster cover with 1/2" sheetrock. for some reason that 8-32 makes the cover perfectly flush with the
Sheetrock. Never had a problem besides there are many bows in todays framing.
 
hbiss said:
Then use a 5/8" raised mud ring.

-Hal
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I agree 5/8" mud ring is proper for 1/2" Sheetrock. The issue is the depth between the block and the inside of the sheetrock is only 1.5" and the 1900 box/cover/screw combination is thicker than that. We've had level 5 finish jobs where they wouldn't accept the bulge in the rock around the boxes.
 
hbiss said:
Bracket boxes are set back to compensate for the thickness of the cover plate and screws which should be flush with the face of the stud. There are times when a box is proud of the stud face and it is noticeable unless the taper levels the area with mud. Good way to PO a fussy GC.

-Hal
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Hal, are you implying that the bracket of the plastic bracketed box should be notched out to be flush with the stud or that it will cause a bulge?
They are roughly the same thickness as the mud ring. I understand the intention of the concern, but in practice, over the years of working with the same GCs and adding new ones every year and getting more and larger projects from them, I have never had even a slight comment from anyone from the GC to the drywall installers about bowing drywall from mudrings on 1900s mounted flush to the stud face.

If any box is installed proud of the stud, then it is installed incorrectly should piss off any GC or EC. In the actual situation of this thread, that isn't very relevant, but it is very true.
 
Don't forget this part of the energy code that applies to wiring. This is directly from the FBC, but is essentially the same verbiage in the other ICC codes. R402.4.1.1 of the energy code.

1) Batt insulation shall be cut neatly to fit around wiring and plumbing in exterior walls, or insulation that on installation readily conforms to available space shall extend behind piping and wiring.

2) Boxes, housings and enclosures that penetrate the air barrier shall be caulked, taped, gasketed or otherwise sealed to the air barrier element being penetrated. All concealed openings into the box, housing or enclosure shall be sealed. The continuity of the air barrier shall be maintained around boxes, housings and enclosures that penetrate the air barrier. Alternatively, air-sealed boxes shall be installed in accordance with Section R402.4.6.

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Rick 0920 said:
It's been years since I've done residential, but when I did a home that used foam board insulation, the inspector allowed me to use a scrap piece of the NM jacket and loop it around the cable, then drive a cut nail (case hard) through the piece of sheath and into the cinder block. It was quick and easy and secured the cable really nice.
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That is a very common and accepted practice in Florida.
 
infinity said:
I agree 5/8" mud ring is proper for 1/2" Sheetrock. The issue is the depth between the block and the inside of the sheetrock is only 1.5" and the 1900 box/cover/screw combination is thicker than that. We've had level 5 finish jobs where they wouldn't accept the bulge in the rock around the boxes.
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Have you ever sighted a a wall with 1/2" sheetrock. 16" centered studs will show bows between the studs. If it a level built around
here than 5/8" is used.
 
kec said:
Have you ever sighted a a wall with 1/2" sheetrock. 16" centered studs will show bows between the studs. If it a level built around
here than 5/8" is used.
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I'm very open to learning new or better installation practices. I can honestly say I do not look at the finish of the drywall of every box my guys install for every project, but in over a decade, the only time there has ever been an issue is if the box was installed improperly and proud of the stud, as mentioned by Hal above. This goes from commercial build-outs of stores and even luxury custom homes 10-25m homes that ive done. Just genuinely confused by this idea of compensating for the flange of the mud rings.
 
Another gripe, I would also be concerned about no 1-1/2" spacing between the NM and back of the sheetrock. I know it only applies to cable next to the studs, but the foam board is rigid and there is only 1/2" space between it and the sheetrock in which to run the cables. Even hanging a picture could conceivably pin the cable to the foam board with a nail and go through it.

The more and more I think about this I agree with Infinity, this is a really bad idea and there is a right way to do it.

infinity said:
You frame a stud wall. You can use metal studs that are only 1 5/8" deep so you don't lose much real estate. Furring strips are for hacks
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-Hal
 
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