What does the last part of this sentence mean exactly?

timber studs: Any cable assemblies closer than 1¼ inches from the front face of the stud need to be protected from damage from drywall screws, and the homeowner hanging pictures, etc. This is achieved by installing a nailing plate on the stud. “Note that the 1¼ inches applies to both sides of the stud if the required distance is not maintained.”


If you are referring to the above sentence, it means that a metal plate may be needed on both sides of the stud. Referring to Jeff’s image above, in figure A, if either of those mesurements are less than 1-1/4, a plate will be needed on that side. And it is possible both of the sides will need a plate if both sides measure less than 1-1/4.


And how is that possible?

Remember that the measurement of 1-1/4" is to the ‘Bored Hole’, not to the actual wire/cable, so (as in the posted graphic) if the hole is centered and larger than 1" in diameter on a standard 2x4, a plate would be needed on both sides.


Plumbing and mechanical have similar codes. P2603.2.1 and G241.7.1

P2603.2.1 Protection against physical damage. In concealed
locations, where piping, other than cast-iron or galvanized
steel, is installed through holes or notches in studs,
joists, rafters or similar members less than 11/4 inches (31.8
mm) from the nearest edge of the member, the pipe shall be
protected by steel shield plates. Such shield plates shall have
a thickness of not less than 0.0575 inch (1.463 mm) (No. 16
Gage). Such plates shall cover the area of the pipe where the
member is notched or bored, and shall extend not less than
2 inches (51 mm) above sole plates and below top plates.

G2415.7 (404.7) Protection against physical damage.
Where piping will be concealed within light-frame construction
assemblies, the piping shall be protected against penetration
by fasteners in accordance with Sections G2415.7.1
through G2415.7.3.

Exception: Black steel piping and galvanized steel piping
shall not be required to be protected.

G2415.7.1 (404.7.1) Piping through bored holes or
notches. Where piping is installed through holes or notches
in framing members and the piping is located less than 11/2
inches (38 mm) from the framing member face to which
wall, ceiling or floor membranes will be attached, the pipe
shall be protected by shield plates that cover the width of
the pipe and the framing member and that extend not less
than 4 inches (51 mm) to each side of the framing member.
Where the framing member that the piping passes through
is a bottom plate, bottom track, top plate or top track, the
shield plates shall cover the framing member and extend
not less than 4 inches (51 mm) above the bottom framing
member and not less than 4 inches (51 mm) below the top
framing member.

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New Building Phase inspectio
No wiring rough-in. No switch or outlet gang boxes. This is billed as an air tight energy efficient home.
Walls furred with 1x3" inch horizontally. All fasteners well over driven more than 50% of the depth of the furring members.
I asked, how are you going to protect circuit cables from damage? 1.5" inch spacing rule. 11/4 inches (31.8 mm) from the nearest edge of the member required.

The cables can be run horizontally 1.25" away from the horizontal framing members. That would still give the cables the required minimum spacing of 1.25".


Thanks Robert.

Hard to do in this case when furring is 1x3" inches. Never seen new building forgo plumbing and electrical rough-in at this stage.

The cables can be stapled to the vertical wood strips as long as they maintain a minimum of 1.25" from the horizontal strips. If they cross behind the horizontal strips then some method to provide the 1.25" spacing would be required.


Hard to do in this case. The furring is 1"x3" inch strips.

This is one way.


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You lost me. Why can’t the cable be stapled 1.25" from the edge of the horizontal strips?

Furring’s are fastened atop wall studs.
Furring’s are fastened to wall studs with the thinnest side facing front to back, horizontally, and the widest sections of furring facing up/down or vertically.

Note: There is less than 1" inch of ‘overall depth’ between every horizontal furring strip and vapour barrier which would be negligible in the event of a nail being able to pernitrate the jacket of a MND90 120V cable. A screw penetrating the jacket of a MND90 120V would likely have a different outcome because of the vapour barrier is not rigid and has some play or flex. The space between each wall stud is less than 1" inch. A stip of metal would need to be installed in the exact orientation as all the wall studs seeing there is not enough clearance to run wiring safely.
I hope this illustration help, Robert.
furring atop wall stud 1

Thank you for the illustration Jim.
Jim, Robert, I am using the orientation wrong. I beg your pardon.
I meant to say, the depth of the cable inside the wall assembly, behind the sheetrock/drywall.
Again, I beg your pardon.

Any cable assemblies closer than 1¼ inches from the front face of the stud needs to be protected from damage from drywall screws, and the homeowner hanging pictures, etc.

The 1.25" dimension is not required to be from the back side of the drywall. It’s only from the framing member that the drywall attaches to. In your photo the framing member that is holding the drywall is the 3" horizontal strip. The cable could be fastened 1.25" above where is says <1" or below that strip to the vertical strip as long as the distance is maintained. This may help clarify what I’m saying from the NECH:


So why do wall stud boring rules differ and a protective metal plate is required.
The electrical circuit wire must be protected from damage . We don’t route electrical wires where they can be punctured by someone driving a nail into a wall to hang a picture. 1-1/4" clearance is required.

I understand the orientation to the edge rule thank you.

Do you? Because that CD graphic is not accurate. It’s easy to see why you have trouble understanding the concept that Mr.Meier is attempting to explain to you.


It is easy to understand why you interrupt. You do not understand the concept.
1-1/4 cable clearance required if the WIRE is within 1/1/4: from the edge of a STUD.

Just to be clear, they can wire the home properly. It appears to me, they got ahead of the selves by insulating and installing the vapour barrier first. I alway watched electricians and plumbers roughed-in plumbing and cables as the wall assemblies were being erected. Insulation and vapour barrier, if any, were installed last just prior sheetrock/wallboard or drywall was installed. The AHJ wanted to inspect all cables and connections before insulation and wallboard was applied.