NM stapled beside furring strips

Coppersmith

Senior Member
Location
Tampa, FL, USA
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
Location
New Jersey
Occupation
Journeyman Electrician
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
Location
Hawthorne, New York NEC: 2014
Occupation
EC
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
Location
Tennessee
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
Location
New Jersey
Occupation
Journeyman Electrician
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
Location
Hawthorne, New York NEC: 2014
Occupation
EC
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
Location
Tampa, FL, USA
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
Location
Tennessee NEC:2017
Occupation
Electrician
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
Location
Chapel Hill, NC
Occupation
Electrical Contractor
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
Location
New Jersey
Occupation
Journeyman Electrician
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
Location
Hawthorne, New York NEC: 2014
Occupation
EC
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
Location
Tampa, FL, USA
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
Location
NE (9.06 miles @5.9 Degrees from Winged Horses)
Occupation
Electrical Contractor
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
Location
New Jersey
Occupation
Journeyman Electrician
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
Location
NE Nebraska
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
Location
Minnesota
Occupation
Electrical Contractor, Electrical Consultant, Electrical Engineer
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
Location
NE Nebraska
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
Location
Minnesota
Occupation
Electrical Contractor, Electrical Consultant, Electrical Engineer
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.
 
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