Electrical wiring in contact with gas pipe, metal water pipe, and HVAC runs

[Jody Humbert]

Had an electrician tell me today that local authority allows electrical wiring to touch metal piping as long as it is insulated and not spliced. I don't believe this is correct and have been calling out any contact as unsafe and recommend rerouting for safety. Any thoughts. Thanks for any comments in advance.

[Jim Port]

The electrical code has no such requirement.

- - - Updated - - -

What are you perceiving as the hazard?

[Jody Humbert]

I was thinking that pest(rodents) damage to the wirings insulation could cause the piping to become energized. I can't see where anyone would logically allow an energized wire to be in contact with a gas line.

[Jerry Peck]

I can't see where anyone would logically allow an energized wire to be in contact with a gas line.

No one is allowing an energized wire to be in contact with a gas line - that is why the wiring has insulation around the conductors and is either in a sheath (such as NM cable) or in a raceway (single wiring such as TW, THW, THHN/THWN, etc.).

When the gas line is installed properly (gas line bonded to ground as required) and the wiring (as NM cable or in a raceway) is installed properly, the hazard is mitigated by both the insulation and outer sheath or insulation and raceway, and, the gas line being bonded to ground.

Kind of like NM cable run through metal studs, the metal studs are bonded to ground.

[Jody Humbert]

SO it is ok for the wiring to be in contact with any piping or HVAC ducting. I will adjust my reporting accordingly. Thanks for your input.

[William Cline]

Section 300.4 in the CEC (California) says "Where subject to physical damage, conductors, raceways, and cables shall be protected." Unfortunately, this leaves latitude for interpretation.
Is the romex supported every 4.5 feet as required?

[Scott Patterson]

SO it is ok for the wiring to be in contact with any piping or HVAC ducting. I will adjust my reporting accordingly. Thanks for your input.

Yep, it is OK..... More home inspector folklore passed down and now quashed for the moment.

[Jerry Peck]

Section 300.4 in the CEC (California) says "Where subject to physical damage, conductors, raceways, and cables shall be protected."

Basically the same as the NEC:
CEC
- 300.4 Protection Against Physical Damage.
- - (A) Cables and Raceways Through Wood Members.
- - - (1) Bored Holes,
- - - (2) Notches in Wood.
- - (B) Nonmetallic-Sheathed Cables and Electrical Nonmetallic Tubing Through Metal Framing Members.
- - - (1) Nonmetallic-Sheathed Cable.
- - - (2) Nonmetallic-Sheathed Cable and Electrical Nonmetallic Tubing.
- - (C) Cables Through Spaces Behind Panels Designed to Allow Access.
- - (D) Cables and Raceways Parallel to Framing Members and Furring Strips.
- - (E) Cables and Raceways Installed Under Roof Decking.
- - (F) Cables and Raceways Installed in Shallow Grooves.
- - (G) Insulated Fittings.

And don't forget
- 300.5 Underground Installations.
- - (A) Minimum Cover Requirements.
- - (B) Wet Locations.
- - (C) Underground Cables Under Buildings.
- - (D) Protection from Damage
- - - (1) Emerging from Grade.
(and the sections go on and on)

[Daniel Robinson]

The only person I have seen call this out is Mike Holmes on tv. I don't unless I see bare wires or not properly secured.

[Raymond Wand]

... but Mike is not a home inspector, he only wants everyone to believe he is one .. Mike is also famous for pointing out something which is against code, but he never ever has quoted code to give his statements legitimacy.

[Jimmy Roberts]

Had an electrician tell me today that local authority allows electrical wiring to touch metal piping as long as it is insulated and not spliced. I don't believe this is correct and have been calling out any contact as unsafe and recommend rerouting for safety. Any thoughts. Thanks for any comments in advance.


You are inventing building and electrical codes to suit your uninformed perception of imagined problems. Also assuming potential rodent damage, when none exists, along with no evidence of rodents.

[John Kogel]

It may not be a code issue, but that does not make it best practice either.

We are used to seeing a wad of fiberglass insulation stuffed between wiring and heat ducts. That is to protect the insulation on the cables from heat and from chafing.

[Chris Weekly]

I dont call out romex contact with piping, but knob and tube wiring is a different story for me.
Even if there is no code requirement, this is a potential danger as deterioration of the old wiring insulation - I call it out, and my recommendation is for an electrical contractor.

[Jim Powlesland]

"Protection Against Physical Damage " is the key . If the contact can damage the wiring it is an issue .

Heat damage should be considered. Flue pipes and electrical wiring are not a good combination. Also, there may be issues with steam piping.

Canadian Electrical Code - Hot Air Ducts or Hot Water Pipes - Rule 12-506(4) requires loomex cable to be kept at least 25 mm (1 in.) away from all hot air heating ducts and hot water piping. A chunk of building insulation may be placed between the cable and the duct or pipe.

NoAm, Book 1, page 57

[bob smit]

Subject to physical damage is the issue if present. Sharp edges on any object should be called out.
One of my favorite rejections is NM cable against the edge of a purlin clip or a truss plate edge.
I made no apologies. When the insulation is installed it usually 'tightens' the cable slack.
Next time you poke your head up a scuttle hole, take a look.:cool:

[Jerry Peck]

One of my favorite rejections is NM cable against the edge of a ... a truss plate edge.

Bob,

About 2-3 weeks ago I was inspecting an Electrical Rough at an apartment building and noticed a pile of white stuff on the floor ... strange, nothing white around here ... I looked up and saw more white stuff at the truss plate under the NM cable - nmmm ... I strained to get a better look that high up, then reached down and picked some of the white stuff up ...

Very thin thread like scraping from the NM cable sheath, the piece I picked up unrolled to over 6 feet long and, based on the pile on the floor and the wad up at the truss plate, I estimated that at least 50-60 feet of the NM cable had been scraped over that truss plate.

The electrician went back and replaced that entire run, and at every truss plate where I saw even a tad of white stuff he replaced those runs too.

I doubt that electrician will do that again after rewiring about 1/4 of the apartment building for having done that all over all three stories of the building (through the roof trusses and floor trusses).

[Dirk Jeanis]

[QUOTE=Jerry Peck;241325
Kind of like NM cable run through metal studs, the metal studs are bonded to ground.[/QUOTE]

I would hope that insulator inserts are used in the steel studs where romex is run. If not gravity and building vibration will possibly cut the insulation in the romex exposing wire to the steel stud.

At least that was the requirement when I worked commercial electrical. We usually used armored runs instead as it was a lot faster and we knew there could never be damage.

[Jerry Peck]

I would hope that insulator inserts are used in the steel studs where romex is run. If not gravity and building vibration will possibly cut the insulation in the romex exposing wire to the steel stud.

At least that was the requirement when I worked commercial electrical. We usually used armored runs instead as it was a lot faster and we knew there could never be damage.

Not only are the plastic bushings installed, they are also snapped, clipped, secured in place as designed - otherwise the bushings can (and do) fall out of place.

Same goes for plumbing piping through metal studs.

[Jim Port]

The bushings are required with metal studs when NM is used.

[Jerry Peck]

The bushings are required with metal studs when NM is used.

They are required, but their use (lack of) and poor installation is one of the things which keeps inspectors employed. :)

[bob smit]

I would hope that insulator inserts are used in the steel studs where romex is run. If not gravity and building vibration will possibly cut the insulation in the romex exposing wire to the steel stud.

At least that was the requirement when I worked commercial electrical. We usually used armored runs instead as it was a lot faster and we knew there could never be damage.

A/C & M/C have the same requirements as NM cable reletive to Mechanical Protection.:rolleyes: