Woven cloth insulation

[kcaj]

I was informed that a building, circa 1928, has recenly had a few fires related ot old wiring with woven cloth insulation. When use the use of cloth insulation for wires outlawed (discontinued) and what is the best procedure for replacing this type of wire ?

 

[physis]

Re: Woven cloth insulation

The wiring should be replaced in compliance with current code.

The first question I can't answer.

 

[ken987]

Re: Woven cloth insulation

I agree with physis it should be rewired.

I've never seen many problems with cloth wire, "IF" it wasn't subjected to over heating. Generally I've found that all the wires in the ceiling box where a light was mounted, usually over lamped had damaged insulation, when stripped back further down the cable the wire was in good shape.

 

[hurk27]

Re: Woven cloth insulation

I just have to say, nothing is really "outlawed" that met code at the time of installation.

This is what grandfather laws is all about.

Now on a more safer note, The wiring in any building that is old should be periodically inspected throughly and replaced as needed. When I mean throughly this means looking at each point of supply and each point of use. Light fixtures cause the most damage to wiring because of the heat that flows up through the outlet box above it. Second look for the heavy loaded circuits and look at the insulation away from connection points. If the insulation is dried out and brittle then this indicates the circuit was over loaded and should be replaced if it is only at the fixtures or where the circuit is connected to the OCPD's then maybe the wire can be reused if the bad section is cut out and new wire is added on to it (I really don't like doing that though). I'm on an apartment building (1940 ish) that I'm rewiring every circuit because the insulation is so bad it crumbles at the slightest touch and causes a short. they had two small fires that were contained to the outlet box's but the insurance company agreed with me that these wires are in bad shape. They even loaned me a snake camera to look inside of the walls and now I have to get one of these

Just keep in mind that old wiring can be safe if it is in good condition and any additions to it have been done in a code compliant way. But with todays appliances you will find circuits overloaded most of the time, and a few Penny's behind a 30 amp fuse

Rewires can be a challenge but it is possible with the right tools with out to much surface disturbance.

 

[peter d]

Re: Woven cloth insulation

I have done my fair share of old-work rewires and it it some of the nastiest work out there. Dirt, mold, plaster dust, asbestos, etc is ever present.

The good news is that there is enough rewiring needed to keep us busy for the next 1000 years.

As Wayne says, the work is challenging and rewarding, and in many cases, long overdue.

 

[Nick]

Re: Woven cloth insulation

A few years ago I did a substation change out in a building that was built in the early 60's. All the feeders were original and had the cloth insulation you are referring to. As Hurk stated heat is the problem. The cables that had been overheated fell apart in your hands. The cables that never got hot were in perfect shape. In fact, the owner elected not to replace them. So anyway, I can tell you it was being installed at least as late as the early 1960's.

 

[physis]

Re: Woven cloth insulation

By Kcaj:

what is the best procedure for replacing this type of wire ?

By Me:

The wiring should be replaced in compliance with current code.

I didn't mean to say that the wiring should be replaced. I meant to say if it is going to be replaced that this is how it should be done.


But if the building keeps catching on fire from the wiring I would recommend replaceing it just because of that.