Old School House Wiring

[Alex Condon]

I've just started rewiring old houses. The doorways are small and the house is beat up. So, it has some sort of cloth covering the wires? What the heck is that about, is that not a fire hazard?

 

[Minder]

Quite common for very old homes, also you will see 'Knob and Tube' style wiring.
A Braided fabric was used for insulation.
https://inspectapedia.com/electric/Old_Electrical_Wiring.php
M.

 

[AnalogKid]

I've just started rewiring old houses. The doorways are small and the house is beat up. So, it has some sort of cloth covering the wires? What the heck is that about, is that not a fire hazard?

Yes, a *huge* one. Remember, UL was formed by a group of insurance companies to deal with the large number of - wait - electrical fires caused by cotton (!!!) insulation.

A friend had to have her whole house re-wired. That was the easy part. The hard part was the requirement to *remove* the old post wiring. Lotsa lathing on the floor.

ak

 

[shrtrnd]

Since you don't know, I'd wear a dust mask when replacing that old wiring.
It's probably the old cotton cloth, but who knows?
Asbestos was not illegal in the good old days.

 

[Bluejets]

Butyl rubber insulation but as in previous post, weave could be asbestos.
These days most countries have facility for testing @ maybe $40. Sample is placed in a tough plastic bag and results come back about a week later.
I have doubts on the effectiveness of a paper mask also.
This can be seriously dangerous and I for one, would give it a wide berth.
Also be aware there are many other sources where asbestos hides in old houses, wall sheeting, floor covering, switchboards and as we recently found, the old bakolite switches.

 

[Tha fios agaibh]

I've just started rewiring old houses. The doorways are small and the house is beat up. So, it has some sort of cloth covering the wires? What the heck is that about, is that not a fire hazard?

Not necessarily.
I have come across many jobs that still have old cloth weave insulation. There is nothing wrong with it provided the integrity of the insulation is still intact. There are circumstances when it should be changed out, such as in a ceiling junction box where the light fixture heat can cook the older 60c temperature rated wire. Codes now require 90c rated wire for such locations.

The old cloth wiring was code compliant at the time of install, and should still be "grandfathered" today provided it doesn't present a safety hazard such as unraveling or cracking conductors from over heating.
But, if your re-wiring houses (major renovation) you should know that you are required to bring everything in the house up to the latest electrical code.
If something is old and questionable, it'd be wise to replace it since the liability is on you.

 

[Alex Condon]

Since you don't know, I'd wear a dust mask when replacing that old wiring.
It's probably the old cotton cloth, but who knows?
Asbestos was not illegal in the good old days.

Wow, I didn't even think of that. Asbestos is bad news. It's such a pain dealing with this, even the breaker looks ridiculous. I think this house was built in the 30's. It's an absolute miracle this house hasn't fallen over. But, the trim in this house is absolutely outstanding. I'm not sure what kind of wood it is on this handrail but it puts the trim in some of these newer houses to shame.