NM stapled beside furring strips

Coppersmith

Senior Member
In a recent inspection, the inspector rejected where I had stapled NM on the side of furring strips citing 300.4D. I thought that only applied to the depth from the face of the wood, not distance from the side of the furring strip. Thoughts?
 

infinity

Moderator
Staff member
Where it's a furring strip or a stud you still need the 1.25" clearance from the front face of the wood. You could attach it to the wall 1.25" away from the edge of the furring strip and that would be code complaint.
 

hbiss

EC, Westchester, New York NEC: 2014
In a recent inspection, the inspector rejected where I had stapled NM on the side of furring strips citing 300.4D. I thought that only applied to the depth from the face of the wood, not distance from the side of the furring strip. Thoughts?
infinity said:
Where it's a furring strip or a stud you still need the 1.25" clearance from the front face of the wood. You could attach it to the wall 1.25" away from the edge of the furring strip and that would be code complaint.
So, how DID you attach the cable to what kind of furring? :?

-Hal
 

augie47

Moderator
Staff member
If the NM is not 1-1/4 from the edge of the strip, the inspector is correct, You can do as Infinity suggests or they do make "Skak-its" designed for the strips.
 

infinity

Moderator
Staff member
I would use a Caddy Colorado Jim strap to hold the NM cable 1.25" away from the edge of the furring strip.
 

hbiss

EC, Westchester, New York NEC: 2014
I thought that only applied to the depth from the face of the wood, not distance from the side of the furring strip.
Apparently he is aware of the 1-1/4" rule. So I'm confused about what he is talking about. Are these the usual 1x furring? Did you just assume that because you only had 3/4" that you could just staple your NM down it and the 1-1/4" rule didn't apply?

The 1-1/4" rule allows you to go horizontally away from the edge of the framing member also in order to comply. So in this case that's the only way to do it. You should have stackers and/or Colorado Jims on your truck- use em'.

-Hal
 

Coppersmith

Senior Member
Apparently he is aware of the 1-1/4" rule. So I'm confused about what he is talking about. Are these the usual 1x furring? Did you just assume that because you only had 3/4" that you could just staple your NM down it and the 1-1/4" rule didn't apply?

The 1-1/4" rule allows you to go horizontally away from the edge of the framing member also in order to comply. So in this case that's the only way to do it. You should have stackers and/or Colorado Jims on your truck- use em'.
The way I understood the rule, if the NM was passing through the stud or furring less than 1.25" from the face, then a metal plate was required to cover it. However I have seen many existing installations where the NM was stapled to the side of the furring. I thought this was allowed since the drywall installers know where the furring is and run their screws down the center of the furring. (Let's not get into a discussion about how incompetent drywall installers are. I agree they are.) I usually use furring standoffs for the NM to avoid problems, but this remodel I'm doing has a lot of existing NM stapled to the sides of furring and I didn't think I needed to change it.
 

Little Bill

Moderator
Staff member
The way I understood the rule, if the NM was passing through the stud or furring less than 1.25" from the face, then a metal plate was required to cover it. However I have seen many existing installations where the NM was stapled to the side of the furring. I thought this was allowed since the drywall installers know where the furring is and run their screws down the center of the furring. (Let's not get into a discussion about how incompetent drywall installers are. I agree they are.) I usually use furring standoffs for the NM to avoid problems, but this remodel I'm doing has a lot of existing NM stapled to the sides of furring and I didn't think I needed to change it.
You have to stay 1-1/4" away from the furring strips.
 

Dennis Alwon

Moderator
Staff member
IMO, if this was an existing install and was approved then I don't see why you would have to change it. If the old job was not permitted then I agree with the inspector.
 

infinity

Moderator
Staff member
300.4 has steel plates in ex's a number of times , with this note>

dies anyone know what 'marked' references ?
:?
~RJ~
The protection plate is required to be a minimum of 1/16". The exception allows for the plate to be less than 1/16" if it is listed and marked.

300.4(A) Cables and Raceways Through Wood Members.
(1) Bored Holes. In both exposed and concealed locations,
where a cable- or raceway-type wiring method is installed
through bored holes in joists, rafters, or wood members,
holes shall be bored so that the edge of the hole is not less
than 32 mm (1 1 ⁄ 4 in.) from the nearest edge of the wood
member. Where this distance cannot be maintained, the
cable or raceway shall be protected from penetration by
screws or nails by a steel plate(s) or bushing(s), at least
1.6 mm ( 1 ⁄ 16 in.) thick,
and of appropriate length and width
installed to cover the area of the wiring.
Exception No. 1: Steel plates shall not be required to
protect rigid metal conduit, intermediate metal conduit,
rigid nonmetallic conduit, or electrical metallic tubing.
Exception No. 2: A listed and marked steel plate less than
1.6 mm ( 1 ⁄ 16 in.) thick
that provides equal or better protec-
tion against nail or screw penetration shall be permitted.
 

hbiss

EC, Westchester, New York NEC: 2014
The way I understood the rule, if the NM was passing through the stud or furring less than 1.25" from the face, then a metal plate was required to cover it. However I have seen many existing installations where the NM was stapled to the side of the furring. I thought this was allowed since the drywall installers know where the furring is and run their screws down the center of the furring.
No different in a regular 2x framed partition or wall. You have to keep 1-1/4" from the face or edge of the stud. It's not assumed that the drywall installers are going to find the studs with any accuracy.

-Hal
 

Coppersmith

Senior Member
No different in a regular 2x framed partition or wall. You have to keep 1-1/4" from the face or edge of the stud. It's not assumed that the drywall installers are going to find the studs with any accuracy.
If I attach a deep new work plastic junction box to a stud and insert an NM cable in the connector closest to the stud, that cable is less than 1.25" from the face of the stud. Please explain why nail plates are not required in this situation.

(I would have liked to post a picture, but alas....)
 

ptonsparky

Senior Member
If I attach a deep new work plastic junction box to a stud and insert an NM cable in the connector closest to the stud, that cable is less than 1.25" from the face of the stud. Please explain why nail plates are not required in this situation.

(I would have liked to post a picture, but alas....)
Because it is not secured to the stud.
 

infinity

Moderator
Staff member
It's also not going to move if a screw starts pushing it. The screw will just go right through it.
You're correct it probably will but it's still not a code violation. Staple it to the stud without the 1.25" clearance and it is a violation.
 

kwired

Electron manager
If I attach a deep new work plastic junction box to a stud and insert an NM cable in the connector closest to the stud, that cable is less than 1.25" from the face of the stud. Please explain why nail plates are not required in this situation.

(I would have liked to post a picture, but alas....)
I take it you are talking about clearance on the back side of wall - I have questioned that myself at times.
 

al hildenbrand

Senior Member
If I attach a deep new work plastic junction box to a stud and insert an NM cable in the connector closest to the stud, that cable is less than 1.25" from the face of the stud. Please explain why nail plates are not required in this situation.
This is where you get to the heart of the matter, in my opinion. This example is about the section of NM cable between the entry to an NM wall box and the first strap securing the NM cable to the stud. This 8" to 12" length of NM cable is NOT installed parallel to the framing member because the cable must come away from the stud surface at the staple at an angle (no longer parallel) to the box entry, therefore it is not covered by the rule describing NM "where installed parallel to the framing member." 2017 NEC 300.4(D). This 8" to 12" is ALMOST parallel, but the Code doesn't say "almost parallel", only parallel.

Where PARALLEL to the framing member OR furring strip, the NM cable has to be 1-1/4" behind or away from the "nearest edge" of the framing or furring, or else it has to be nailplated. To me, the huge hole in this concept concerns the nailplating strategy. When NM cable is going through framing in holes or notches, the nailplate only covers the framing, not the additional 1-1/4" on either side of the framing; AND, in the case of your example that I quote above, the NM cable that is not parallel to the framing / furring doesn't have a requirement for nailplating, in my opinion.

In my experience, AHJs have differing opinions about this.
 

kwired

Electron manager
This is where you get to the heart of the matter, in my opinion. This example is about the section of NM cable between the entry to an NM wall box and the first strap securing the NM cable to the stud. This 8" to 12" length of NM cable is NOT installed parallel to the framing member because the cable must come away from the stud surface at the staple at an angle (no longer parallel) to the box entry, therefore it is not covered by the rule describing NM "where installed parallel to the framing member." 2017 NEC 300.4(D). This 8" to 12" is ALMOST parallel, but the Code doesn't say "almost parallel", only parallel.

Where PARALLEL to the framing member OR furring strip, the NM cable has to be 1-1/4" behind or away from the "nearest edge" of the framing or furring, or else it has to be nailplated. To me, the huge hole in this concept concerns the nailplating strategy. When NM cable is going through framing in holes or notches, the nailplate only covers the framing, not the additional 1-1/4" on either side of the framing; AND, in the case of your example that I quote above, the NM cable that is not parallel to the framing / furring doesn't have a requirement for nailplating, in my opinion.

In my experience, AHJs have differing opinions about this.
Good technical description of how it may be excluded from NEC - still in somewhat of a danger zone for being pierced by a nail or screw that missed the stud when hanging the drywall
 

al hildenbrand

Senior Member
Good technical description of how it may be excluded from NEC

Thanks. First start with what the Code actually says. . . that's the minimum installation required by the text, by the "Holy Writ".


still in somewhat of a danger zone for being pierced by a nail or screw that missed the stud when hanging the drywall
Yes, there are bits of additional, beyond-NEC-minimum installation that will make a roughin harder for rockers, et. al., to damage.
 

al hildenbrand

Senior Member
So you can zig zag up the furring bay by stapling to the furring strip on one side, then the other, and it's all good, as it's only "almost parallel"?
Yeah, we've played these word games before. . .or maybe its a math definition game, . . . or maybe it is what I'm typing right now: It's an abstracted game about a game.

Whatever.

Side stepping your parry, I lift up Rob's near perfect zen koan of "installing parallel to":
You're correct it probably will but it's still not a code violation.
Staple it to the stud without the 1.25" clearance and it is a violation.
 

hbiss

EC, Westchester, New York NEC: 2014
It's also not going to move if a screw starts pushing it. The screw will just go right through it.
I've stated my position on this before. It should be prohibited to run wiring within a 1x furred wall cavity. No matter how you do it it's never going to be 1-1/4" from the back of the sheetrock. The Code doesn't think that's important but a screw or nail in the right place is going to get the cable.

-Hal
 

kwired

Electron manager
I've stated my position on this before. It should be prohibited to run wiring within a 1x furred wall cavity. No matter how you do it it's never going to be 1-1/4" from the back of the sheetrock. The Code doesn't think that's important but a screw or nail in the right place is going to get the cable.

-Hal
With that approach one must assume nothing will ever penetrate the wall more than 1-1/4 inches beyond the framing either - not true. The risk is simply higher near the framing members. I've seen longer than needed nails or screws used many times to fasten all sorts of items to a wall, that 1-1/4 rule just helps prevent mishaps from some of the most common things out there.
 

hbiss

EC, Westchester, New York NEC: 2014
With that approach one must assume nothing will ever penetrate the wall more than 1-1/4 inches beyond the framing either - not true. The risk is simply higher near the framing members. I've seen longer than needed nails or screws used many times to fasten all sorts of items to a wall, that 1-1/4 rule just helps prevent mishaps from some of the most common things out there.
True. But after a wall is finished, nobody knows where the studs are, or they aren't even looking for them, least of all homeowners. At least with 2x framing the nail or screw can push the cable back, especially with Colorado Jims that allow movement and the cable is probably more than 1-1/4" from the back of the sheetrock also. But with only 3/4" behind the sheetrock, it's guaranteed that even a 1" screw or nail is going to pin the cable back against the concrete and penetrate it. The odds become exponentially greater for damage.

-Hal
 

al hildenbrand

Senior Member
True. But after a wall is finished, nobody knows where the studs are, or they aren't even looking for them, least of all homeowners. At least with 2x framing the nail or screw can push the cable back, especially with Colorado Jims that allow movement and the cable is probably more than 1-1/4" from the back of the sheetrock also. But with only 3/4" behind the sheetrock, it's guaranteed that even a 1" screw or nail is going to pin the cable back against the concrete and penetrate it. The odds become exponentially greater for damage.

-Hal
Sounds like you should make a proposal for the 2023 NEC.
 

hbiss

EC, Westchester, New York NEC: 2014
They will just say that AFCIs will take care of it. :weeping:

-Hal
 

jap

Senior Member
The protection plate is required to be a minimum of 1/16". The exception allows for the plate to be less than 1/16" if it is listed and marked.


300.4(A) Cables and Raceways Through Wood Members.
(1) Bored Holes. In both exposed and concealed locations,
where a cable- or raceway-type wiring method is installed
through bored holes in joists, rafters, or wood members,
holes shall be bored so that the edge of the hole is not less
than 32 mm (1 1 ⁄ 4 in.) from the nearest edge of the wood
member. Where this distance cannot be maintained, the
cable or raceway shall be protected from penetration by
screws or nails by a steel plate(s) or bushing(s), at least
1.6 mm ( 1 ⁄ 16 in.) thick,
and of appropriate length and width
installed to cover the area of the wiring.
Exception No. 1: Steel plates shall not be required to
protect rigid metal conduit, intermediate metal conduit,
rigid nonmetallic conduit, or electrical metallic tubing.
Exception No. 2: A listed and marked steel plate less than
1.6 mm ( 1 ⁄ 16 in.) thick
that provides equal or better protec-
tion against nail or screw penetration shall be permitted. [HR][/HR]
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Unless there's a code section that explains it more clearly, I, like Coppersmith, would like to know where in above statement it indicates that the cable must be kept 1 1/4" away from the face of the stud.

If nailing the cable to the side of a furring , you're not going through a wood member or through a bored hole.

The whole thing about the cable entering an outlet box connector at "not exactly parallel to the framing member for 8 or 12 inches" just seems silly to me.

JAP>
 

kwired

Electron manager
Unless there's a code section that explains it more clearly, I, like Coppersmith, would like to know where in above statement it indicates that the cable must be kept 1 1/4" away from the face of the stud.

If nailing the cable to the side of a furring , you're not going through a wood member or through a bored hole.

The whole thing about the cable entering an outlet box connector at "not exactly parallel to the framing member for 8 or 12 inches" just seems silly to me.

JAP>
I agree, yet many still think that if it is secured to the side of the stud it must be 1-1/4 from the face of the stud, when in fact the wording only mentions bored holes. Good design practice is still to keep away from areas more likely to have something penetrate though - but that is good practice not code requirement.
 

jap

Senior Member
I agree, yet many still think that if it is secured to the side of the stud it must be 1-1/4 from the face of the stud, when in fact the wording only mentions bored holes. Good design practice is still to keep away from areas more likely to have something penetrate though - but that is good practice not code requirement.
So why are so many defending a rule where that's not actually what it says?

JAP>
 

jap

Senior Member
By the wording, to me, the OP is correct and understood the rule more so than the inspector.

Unless there's some wording otherwise that I'm not aware of.

JAP>
 

jap

Senior Member
Apparently he is aware of the 1-1/4" rule. So I'm confused about what he is talking about. Are these the usual 1x furring? Did you just assume that because you only had 3/4" that you could just staple your NM down it and the 1-1/4" rule didn't apply?

The 1-1/4" rule allows you to go horizontally away from the edge of the framing member also in order to comply. So in this case that's the only way to do it. You should have stackers and/or Colorado Jims on your truck- use em'.

-Hal
That's exactly what I would assume.

What part of the rule states that you can't ?

If you have a 1x furring strips which are generally 3/4" thick 2 or 3" wide attached to a block wall, and you're running NM along side that furring strip, how does moving the cable horizontally any distance away from the side of the furring strip make it any more safe?

It doesn't.

You don't gain any more than 3/4" of an inch clearance no matter where you move the cable in the void.

JAP>
 

al hildenbrand

Senior Member
By the wording, to me, the OP is correct and understood the rule more so than the inspector.

Unless there's some wording otherwise that I'm not aware of.

JAP>
The OP is not asking about bored holes in furring. Rob introduced 300.4(A)(1) to talk about nail plates. For the OP scenario, his inspector saw a 300.4(D) situation. 300.4(A)(1) does not apply.

So the "wording" is in 300.4(D).
 

jap

Senior Member
The OP is not asking about bored holes in furring. Rob introduced 300.4(A)(1) to talk about nail plates. For the OP scenario, his inspector saw a 300.4(D) situation. 300.4(A)(1) does not apply.

So the "wording" is in 300.4(D).
That's wording I was looking for.

I agree with the inspector now. :)

JAP>
 

PaulMmn

Senior Member
I hesitate to say it, in fear of another chapter in the code--

Does the problem go away if the wiring is in metal conduit? (EMT or BX)

It's either that or surface-mounted panduit or wiremold...
 

jap

Senior Member
I hesitate to say it, in fear of another chapter in the code--

Does the problem go away if the wiring is in metal conduit? (EMT or BX)

It's either that or surface-mounted panduit or wiremold...
I'd bet it does, . :)

JAP>
 

al hildenbrand

Senior Member
I hesitate to say it, in fear of another chapter in the code--

Does the problem go away if the wiring is in metal conduit? (EMT or BX)

It's either that or surface-mounted panduit or wiremold...
Armored Cable, AC, has to be protected like NM, (2017 NEC 320.17).

EMT is safe, with exception of "severe" physical damage, therefore Article 358 does not invoke 300.4.

Edit to add: MC has to be installed per 300.4 (2017 NEC 330.17).
 

infinity

Moderator
Staff member
The OP is not asking about bored holes in furring. Rob introduced 300.4(A)(1) to talk about nail plates. For the OP scenario, his inspector saw a 300.4(D) situation. 300.4(A)(1) does not apply.

So the "wording" is in 300.4(D).
Yes if you go back to my original post the question and answer with the code reference was what it meant when the nail plate was referred to as "marked".
 

kwired

Electron manager
I hesitate to say it, in fear of another chapter in the code--

Does the problem go away if the wiring is in metal conduit? (EMT or BX)

It's either that or surface-mounted panduit or wiremold...
EMT doesn't need nail plates, see the exceptions in 300.4 sections mentioned. That said I have seen drywall screws penetrate EMT a few different times, so I still try to avoid placing it too close to the stud when possible if it is going to be close to the finish covering.
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Colorado Jims are easier to screw on and fasten than stapling to the edge of a furring strip anyway.
 

Coppersmith

Senior Member
Like I said above, I normally use nail-on standoffs on furring. Not because I thought I was required to, but just because I expect the drywallers to be incompetent. My main complaint was the inspector was forcing me to fix existing work. I did so and passed a re-inspection. There are definitely inconsistencies in how NM wiring is handled in the NEC.

https://www.walmart.com/ip/3M-SIFS-1-Furring-Strip-Cable-Stacker-White-PK250/148235721
 
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al hildenbrand

Senior Member
My main complaint was the inspector was forcing me to fix existing work.
Yeah, that's hard, . . . I imagine this wasn't revealed to you until after your bid was fixed, and then the wall covering was removed.

In my area, they say I have to correct "obvious Code violations" if they are within the scope of my work.

The requirement that is today's 300,4(D) is decades old . . . do you think the materials of the old installation clearly indicate they were inspected, or that they were installed before the Code requirement existed?
 

Coppersmith

Senior Member
Yeah, that's hard, . . . I imagine this wasn't revealed to you until after your bid was fixed, and then the wall covering was removed.

In my area, they say I have to correct "obvious Code violations" if they are within the scope of my work.

The requirement that is today's 300,4(D) is decades old . . . do you think the materials of the old installation clearly indicate they were inspected, or that they were installed before the Code requirement existed?
Nothing I see in this house leads me to believe it wasn't inspected when it was built. I have seen NM stapled to the sides of furring in many existing houses. Must be the inspectors allowed it.
 

al hildenbrand

Senior Member
Nothing I see in this house leads me to believe it wasn't inspected when it was built. I have seen NM stapled to the sides of furring in many existing houses. Must be the inspectors allowed it.
If you have seen so much, what does the local head of the Authority Having Jurisdiction have to say. If any one would know of the historic variations for your job's jurisdiction, that's the person to talk to.
 
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