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John Naehring
09-06-2009, 12:51 PM
Is this allowed? I am working on a friends 1820's house, we replaced a light fixture and found out that all the wire insulation was flaking off, All the wire is in BX armor, we need to re-wire a 3 way switch and the easiest path to run the 3 wire to the other switch is to go straight down between the plaster and the chimney into the basement and up the other wall, is this legal?

Bill Kriegh
09-06-2009, 04:26 PM
Yes.

Just make sure you follow the rules for the areas where the cable is exposed.

Jerry Peck
09-06-2009, 07:12 PM
Yes.

Just make sure you follow the rules for the areas where the cable is exposed.

Bill,

He is talking about using NM cable for the re-wire, so what about clearance from combustible material for the chimney?

Brandon Whitmore
09-06-2009, 09:05 PM
I've got another question along with this one. On re- wire jobs, how do contractors get away with not properly securing the Romex wires when fished up through walls, chases, adjacent to chimneys, etc.? Is it not required on retro- fits?

Jerry Peck
09-07-2009, 06:13 AM
On re- wire jobs, how do contractors get away with not properly securing the Romex wires when fished up through walls, chases, adjacent to chimneys, etc.? Is it not required on retro- fits?

- 334.30 Securing and Supporting.
- - Nonmetallic-sheathed cable shall be supported and secured by staples, cable ties, straps, hangers, or similar fittings designed and installed so as not to damage the cable, at intervals not exceeding 1.4 m (4½ ft) and within 300 mm (12 in.) of every outlet box, junction box, cabinet, or fitting. Flat cables shall not be stapled on edge.
Sections of cable protected from physical damage by raceway shall not be required to be secured within the raceway.
- - (A) Horizontal Runs Through Holes and Notches. In other than vertical runs, cables installed in accordance with 300.4 shall be considered to be supported and secured where such support does not exceed 1.4-m (4½-ft) intervals and the nonmetallic-sheathed cable is securely fastened in place by an approved means within 300 mm (12 in.) of each box, cabinet, conduit body, or other nonmetallic-sheathed cable termination.
- - - FPN: See 314.17(C) for support where nonmetallic boxes are used.
- - (B) Unsupported Cables. Nonmetallic-sheathed cable shall be permitted to be unsupported where the cable:
- - - (1) Is fished between access points through concealed spaces in finished buildings or structures and supporting is impracticable.
- - - (2) Is not more than 1.4 m (4½ ft) from the last point of cable support to the point of connection to a luminaire or other piece of electrical equipment and the cable and point of connection are within an accessible ceiling.

ken horak
09-07-2009, 06:24 AM
Bill,

He is talking about using NM cable for the re-wire, so what about clearance from combustible material for the chimney?

First one must determine the make up of the chimney. Masonary ? Stove pipe ?

Jerry Peck
09-07-2009, 06:28 AM
First one must determine the make up of the chimney. Masonary ? Stove pipe ?

The difference is only a matter of a few inches, if any difference, and 'most likely' the clearances do not meet to required clearances anyway - meaning the NM cable would be running next to the chimney within the clearance space.

Besides, with an 1820s house the presumption is a masonry chimney.

Bill Kriegh
09-07-2009, 06:48 AM
334.116 Sheath. The outer sheath of nonmetallic-sheathed
cable shall comply with 334.116(A), (B), and (C).
(A) Type NM. The overall covering shall be flame retardant
and moisture resistant.



ARTICLE 334
Nonmetallic-Sheathed Cable:
Types NM, NMC, and NMS
334.30 Securing and Supporting.
(B) Unsupported Cables. Nonmetallic-sheathed cable
shall be permitted to be unsupported where the cable:
(1) Is fished between access points through concealed
spaces in finished buildings or structures and supporting
is impracticable.

One purpose of fastening NM-B on new work is to (hopefully) prevent the penetration of nails and screws used to fasten the wall covering. You never are going to prevent a homeowner from driving a 16p nail into a wall to hold up grandma's picture and penetrating a cable in the process. Actually, unfastened cables inside a wall have a bit of an advantage here as they can often be pushed out of the way by the nail or screw.

Bill Kriegh
09-07-2009, 06:55 AM
Well, I see a couple of folks posted between the time I started a reply and got called to the phone.

Every AHJ I've ever asked about running NM-B in these spaces has basically said that it's not framing material and it doesn't support combustion.

Jerry Peck
09-07-2009, 08:33 AM
Every AHJ I've ever asked about running NM-B in these spaces has basically said that it's not framing material and it doesn't support combustion.

And what about the heat from the chimney which is the reason for the clearance to combustible material, heat as regarding ambient temperature and derating? Would one then need to account for that heat for derating?

Also, "flame retardant" is not the same as being 'non-combustible', leaving it still as a "combustible material", right?

The AHJ which I've asked were left pondering the question, saying "I'd need to see the installation and make my decision at the time of inspection.", basically putting off committing to anything without getting time to think it over. :)

Michael Garrity
09-07-2009, 11:56 AM
Is it wood lathe and plaster?If so, is there enough room to run a length of metal conduit between the brickwork and the lathe starting in the basement?

Brandon Whitmore
09-07-2009, 01:13 PM
Thanks Jerry,

Don't know how I read past that one:o

Brandon Whitmore
09-07-2009, 01:45 PM
Is there any reason to purchase the 2008 version of the NEC, if I purchase the NEC Handbook version. I am assuming that the entire NEC is on the Handbook version-- is that correct?


2008 NEC on CD: Access the latest rules for electrical installations, including first-time articles, revised requirements for AFCI and GFCIs in dwellings, and the new provisions that reduce worker hazards and correlate with NFPA 70E®. View text with or without shading behind changes, so you can see what’s new in the Code. Search, print, or cut and paste text or graphics, or bookmark text for fast retrieval. Also includes the 2005, 2002, and 1999 NEC archive editions as PDF view only. (CD-ROM)
2008 NEC Handbook on CD: Gain instant access to exclusive commentary on the 2008 Code, including coverage of new articles and 500+ full-color illustrations that enhance your understanding of even the toughest requirements. Search, print, or cut and paste text or graphics from the entire NEC Handbook or 2008 NEC. No other resource offers so much information about electrical safety! Also includes the 2005 and 2002 NEC editions as PDF view only for cross-referencing. (CD-ROM)

Thanks.

Brandon Whitmore
09-07-2009, 09:30 PM
Thanks Ben.

ken horak
09-08-2009, 07:12 AM
The NFPA version of the handbook has the entire NEC in it.
The NFPA version of the handbook is the NEC with pictures,and explanations

The key point is : NFPA.

Jerry Peck
09-08-2009, 12:20 PM
The NFPA version of the handbook has the entire NEC in it.
The NFPA version of the handbook is the NEC with pictures,and explanations

The key point is : NFPA.


Agreed, and I would recommend getting BOTH.

Jerry Peck
09-08-2009, 12:39 PM
JP. Just curious. How often do you use the CD in the field? I find the NFPA CD is way over touted and priced. I find tracking and marking the 70 a lot quicker. CD is a waste of $$$. JMO rbj

I have the NEC in print AND on CD (actually on my computer).

I have the Handbook in print. I would like to have the Handbook on CD too.

To answer your question, though, basically never, because I keep the Handbook in my office. If I had it on CD (on my computer) I would have it available in the field.

I also have the UL White Book in print AND on my computer.

I guess you would say that I waste too many $$$?

mathew stouffer
05-25-2011, 06:19 AM
DIY. Check out this beaut. Does running is over ducts count as support;)

Ted Menelly
05-25-2011, 09:07 AM
DIY. Check out this beaut. Does running is over ducts count as support;)

That is a pretty busy mess including the gas line running thru joist after joist. I guess every trade must have been there at the same time running their materials stepping over the other contractors seeing who could get it run first.

Jerry Peck
05-25-2011, 05:57 PM
DIY. Check out this beaut. Does running is over ducts count as support;)

:D

(bold and underlining is mine)
334.30 Securing and Supporting.
- Nonmetallic-sheathed cable shall be supported and secured by staples, cable ties, straps, hangers, or similar fittings designed and installed so as not to damage the cable, at intervals not exceeding 1.4 m (4½ ft) and within 300 mm (12 in.) of every outlet box, junction box, cabinet, or fitting. Flat cables shall not be stapled on edge.
Sections of cable protected from physical damage by raceway shall not be required to be secured within the raceway.

" ... shall be supported AND SECURED ... at intervals not exceeding ... "

I guess as long as they SECURE the NM cables to the ducts that the NM cables are laying on, that would count ... NOT! :D

H.G. Watson, Sr.
05-26-2011, 05:32 AM
Mat,

No. See "exposed work".

Note nails at top left corner of plywood upon wall beyond low vent headroom egress obstruction at door, clearance as well. cables are neither protected from damage nor secured to structural.

Regarding other photo with flex duct - bare incandescent producing heat, zip cord, commuications cabling, etc. Cables are "supporting" flex duct, straining conductors. Unsupported copper tube, and CCST running through via hole in PRI - apparently - THROUGH - a return air cavity (sheet metal , apparently unlined and questionably "enclosed"); and similarly unsupported or secured, interesting ra. bend. The pex straddling and supported by the bare lamp (bulb) and the sagging flex duct is funny. That 12 ga. NM too small to be under bottom chords esp wrapped around fixture box.

Lets see, what wattage "bulb" was used in those easy bake ovens to bake a cake...which would happen first - cold water inrush pex contracting and bulb shattering or pex expansion from direct and radiant contact heat excessive temperatures, IR, and deteriorating from UV emitted from incandenscent, etc. and a geyser/flood.