Tin coated copper question

Did all the tin coated copper have fabric sheathing?

Picture did not show up, but it looks like aluminum wiring with plastic coating.
Due to the age of the house I was thinking it might be tin coated copper.

1947 house but has had electrical work over the years…

Plainly put, I don’t know. What I can say for sure is that I’ve never seen tin plated copper conductors that weren’t part of a fabric covered cable. If I saw a silver-ish colored conductor with thermoplastic insulation, I’d suspect aluminium way before I’d suspect tin plate. I can visually tell the difference, but only because I’ve seen a heck of a lot of both. Probably harder for someone else.


If I cant tell in the panel, (easier to look at it on the ground buss bar) and it has plastic sheathing I alway try to find it in the attic or crawl space. The romex will have “Alumaflex” or “Kaiser Aluminum”, “KA-Flex” etc. Usually pretty easy to find and identifiable in these areas.

You can really see the solid alum on the buss bar. And I found it in the attic to confirm.

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General Rule of Thumb…if it has thermoplastic insulation on the conductor and it is shiny AL colored…probably AL wiring. If the jacket is spongie or rubberish in nature and before the 70’s…chances are Tinned Copper.

All AL single strand I am aware of has thermoplastic insulation…atleast all I have seen…but thats not gospel…:slight_smile:

Here…this might help ya - http://www.inspect-ny.com/aluminum/recogniz.htm

Agree also with you comments.

You need to take into consideration the age of the home and improvements completed (time) into your overall assessment of the home’s condition.

I just cannot understand why they use aluminum when it is such a problem for everyone.

When it was being used, it wasn’t really known that it was going to be such a problem.

As I understand it, it was brought in as a cheaper alternative to copper when the huge increase in the stock market in gold, silver, and copper in the late 60’s/early 70’s. Prices went through the roof…hence the much cheaper alternative. Gov’t jumped on board, approved it, and here we are.

Vietnam war time. Military was using a lot of copper.

Bruce, I think the answer is “yes.” I’ve always known tin-coated copper wiring as “Jute.” I can’t remember when or where I learned this, and I may be completely wrong, but believe the name has to do with the rubbery material from which the sheathing is made.

Another fine product that deteriorates on touch.