Knob and Tube circuit extensions

[TSET]

(Quote from seperate post of mine, yesterday)
"I searched "Knob..." on the archives. I was a bit discouraged, possibly abit confused by the information I found there. The Job that I am looking at has the typical new-to-old splicing nasties that I'm sure most of you have seen, plus some J-boxed work that, on the surface, looks pretty good, but I'm sure was unpermitted.
From what I could glean(sp) from the posts, it sounds like you can feed old K&T from new romex, but not the reverse? I don't want to get into soldering (especially in a hot attic), so J-boxing is the way to go, but the flying neutral-only, or hot-only splices need re-work, containment, and jumpers. It seems, from my reading, that there is no allowed single conductor or Romex usage for thse jumpers. Its a rule for me never to use old wire in repairs, due to unknowns, so it seems there is no repair option, for some of this work, just replacement. Have I read this right?"

TODAY
RE:394.10 (1).
"...knob and tube shall be permitted...as follows: (1) For circuit extensions of existing installations"
So for the purposes of the repair (to be inspected), using a NM box for the splices, with intregal clamps, and following the guidelines of the official NEC 2005 handbook, it would seem that THHN is an acceptable conductor (exposed/visible) as per the added note of explanation in the handbook, "Conductors used for knob and tube work may be of any general use type specified by Article 310."
This repair is needed to resolve mid-air flying splices (spider web splicing) in the attic. This is not truly an extension, as I think of an extension (as in adding another receptacle).
Does anyone see a conflict within the bounds of the code for this action?

 

[e57]

The safest bet is to look in your local codes for any alteration of the wording in 80.9(C), AND ask your local inspector. These "flying splices" may only be in need of proper support.

See 394.30, and 394.56.

I'm sure there will be some debate about what an "appoved splicing device" is. To some that is a clean conductor with a Western union, or a pigtail and soldered, cleaned again, and taped with rubber and friction. To others termaflex (Crap tape) will do. To some a crimp... And to others still, a wire nut... Taped or not... (Personally, if you not going to solder it, tape the splice to the supported conductors, if only for neatness sake.) IMO, if you are uncomfortable with soldering you shouldn't. Some call it an art - it is not, it is a skill, and an easy one with some practice once you know the technique. Splicing, is also not an art, but it too is an easy skill to learn.

http://www.markhellerelectric.com/wusplice.pdf
http://www.markhellerelectric.com/solder.pdf
http://www.markhellerelectric.com/solder2.pdf

 

[iwire]

The safest bet is to look in your local codes for any alteration of the wording in 80.9(C),

Is there any area at all that uses Article 80?

ARTICLE 80 Administration and Enforcement

This article is informative unless specifically adopted by the local jurisdiction adopting the National Electrical Code?. (See 80.5.)

80.5 Adoption.

Article 80 shall not apply unless specifically adopted by the local jurisdiction adopting the National Electrical Code.

Article 80 is no longer even in the front of the code book, it's now tucked away in an Annex I suspect it's from lack of use that it was moved.

 

[e57]

I was thinking of this wording: (2002 NEC, and I think most states replace most of this administration text?)

80.9(C) Additions, Alterations, or Repairs. Additions, alterations, or repairs to any building, structure, or premises shall conform to that required of a new building without requiring the existing building to comply with all the requirements of this Code. Additions, alterations, installations, or repairs shall not cause an existing building to become unsafe or to adversely affect the performance of the building as determined by the authority having jurisdiction. Electrical wiring added to an existing service, feeder, or branch circuit shall not result in an installation that violates the provisions of the Code in force at the time the additions are made.

Anyway my point was about how the AHJ would look at alterations and repairs of existing wiring.

Sorry to say, I still have a little under 6 months to get a new code book... Holding out for the time being.

 

[TSET]

soldering & taping?

soldering & taping?

Thanks for the replies, and thanks Mark, for the emails, I'm still perusing, but they look helpful. I'm in Bremerton, Wa, and I'll be talking with the inspector(s) tomorrow before the job. I have assumed that soldering isn't necessary, as long as the splices were in a box (nm) and with approved conn. (wire nut). Do I then still have to tape it?

 

[e57]

394.30 Securing and Supporting.
(A) Supporting. Conductors shall be rigidly supported on noncombustible, nonabsorbent insulating materials and shall not contact any other objects. Supports shall be installed as follows:
(1) Within 150 mm (6 in.) of each side of each tap or splice, and
(2) At intervals not exceeding 1.4 m (41/2 ft).
Where it is impracticable to provide supports, conductors shall be permitted to be fished through hollow spaces in dry locations, provided each conductor is individually enclosed in flexible nonmetallic tubing that is in continuous lengths between supports, between boxes, or between a support and a box.
(B) Securing. Where solid knobs are used, conductors shall be securely tied thereto by tie wires having insulation equivalent to that of the conductor.
394.42 Devices.
Switches shall comply with 404.4 and 404.10(B).
394.56 Splices and Taps.
Splices shall be soldered unless approved splicing devices are used. In-line or strain splices shall not be used.

OK this may sound contrary to everything you may have ever learned about electrical work, but... (It's an older method that you are repairing)
Splices in this wiring method do not necessarily need to be in a box... They need to be supported, within 6". (As well as complying with 394.19) One way to support the splice is to tape it to a conductor that is supported to train it from being loose and violating the clearances in 394.19. (1" from framing and other surfaces, 3" from other conductors unless there is loom or a tube taped in place, and not less than 2" from from pipe or other conductors with a tube taped in place) The only items that need to be in a box are devices (Switches, and recepticals) and lighting junctions. If they are to go into a box you would need loom for the loose conductor from the last support to the box entrance... And if your AHJ accepts a wire nut as an approved splicing device, you would not need to solder... As mentioned before, the repair, and method of repair are up to the AHJ. That is if repair is even necessary, as you are still in the thinking that all splices need to be in a box - they don't, they just need to be properly supported.

Attached is an image of a normal soldered K&T splice, and one with a wire nut splice trained to maintain clearances, and taped to itself. As I said before soldering is the preffered method, but you do not seem confident with soldering... See if your inspector is OK with a supported wire nut... He may even be OK with leaving that <6" of conductor free???