Reusing existing wire

[mkgrady]

I'm doing a kitchen remodel and am wondering how much of the existing wire can be re-used. I have done the demo to all the wiring except I saved all the home runs. They enter the kitchen from a crawl space below. It appears there are enough home run circuits to serve all the new branch circuits required but I want to confirm my thinking that using these NM's is allowed. The existing NM cable appears to be about 20 years old and in good condition. I want to re-use the home runs because running new ones would be very difficult (very shallow crawl space). I plan to have all the home runs come into a large (12"x12") JB behind one of the base cabinets. Most of these home runs will not reach their first destination box. Almost all the home runs are MWBC's and about half of them come from a standby generator panel with the usual automatic transfer switch arrangement.

 

[chris kennedy]

The existing NM cable appears to be about 20 years old and in good condition.

Full size EGC?

 

[mkgrady]

Full size EGC?

Yup, All that I checked so far.

 

[480sparky]

I'd say that as long as the sheath and insulation are good, then by all means reuse it.

If you're going into a 12x12 jbox behind a base cabinet, make sure it gets cut out and there will be no shelves or drawers to interfere with future access to it.

 

[chris kennedy]

If you're going into a 12x12 jbox behind a base cabinet, make sure it gets cut out and there will be no shelves or drawers to interfere with future access to it.

Now that I think about it 20 years ago was 87. Of course they would have a full size EGC.

And Ken, whats the problem with shelves and drawers? Just take them out.

Accessible or readily accessible?

 

[celtic]

Accessible or readily accessible?

Accessible

If readily was the case....you'd never be able to put a 1900 box (4S) in a drop ceiling

 

[mkgrady]

Thanks for all the replies.

 

[480sparky]

And Ken, whats the problem with shelves and drawers? Just take them out.

Accessible or readily accessible?

Some cabinets don't have them removable. Been there, done that!

 

[mdshunk]

I'm not even sure I'd bother with the big jbox arrangement. Just end them in a box or boxes in the crawl space, and drop all your new tails down to the crawl. Why needlessly frustrate the cabinet guy or the GC? I've done the big jbox thing in a cabinet or flush behind a fridge before, but not when there's a perfectly good crawl space or attic space to use.

 

[brantmacga]

I'm not even sure I'd bother with the big jbox arrangement. Just end them in a box or boxes in the crawl space, and drop all your new tails down to the crawl. Why needlessly frustrate the cabinet guy or the GC? I've done the big jbox thing in a cabinet or flush behind a fridge before, but not when there's a perfectly good crawl space or attic space to use.

marc i was betting money that your reply was going to say something about a megger. oh well.

 

[Pierre C Belarge]

marc i was betting money that your reply was going to say something about a megger. oh well.

I was thinking the same..."megger Marc"... that is. :wink:

By reusing the existing homeruns that are approximately 20 years old, I would have a couple of thoughts, especially since you did not perform the original installation.
What kind of actions could have occurred since the original installation - mice, other environmental conditions such as moisture, dirt, pinching of cable due to building settling, or any of the other myriad items that could occur over a 20 year period of time. (condition of insulation due to ckt usuage, etc...).

Without being able to physically see the cables, a megger does help in getting an idea of conductor insulation values, even if it is only point of time.Also, since it is only HRs, it would be relatively easy and less time consuming than normal for the testing procedure.

Me, I do not like reusing existing wiring in a new installation.

 

[mkgrady]

I'm not even sure I'd bother with the big jbox arrangement. Just end them in a box or boxes in the crawl space, and drop all your new tails down to the crawl. Why needlessly frustrate the cabinet guy or the GC? I've done the big jbox thing in a cabinet or flush behind a fridge before, but not when there's a perfectly good crawl space or attic space to use.

The crawl space is VERY tight. I would not want to be the guy to go check a splice in the future. Of course I will make the best quality splices I can and there should never be a reason to go to the JB's but I'll be the only one who knows that.

 

[mdshunk]

Hey, you know... while you're at it, you might as well megger those home runs. :wink:

 

[peter d]

That's the Marc we all know!

 

[Michael15956]

The J-box only needs to be accessible, not readly accessible, 314.29.

 

[LawnGuyLandSparky]

I would try to terminate as many homeruns as possible at a countertop outlet, and only use a junction box behind a base cabinet if absolutely necessary. If 2 cables enter a 4&11/16 box with a single gang mud ring, that's 4 circuits down right there.

 

[mkgrady]

I would try to terminate as many homeruns as possible at a countertop outlet, and only use a junction box behind a base cabinet if absolutely necessary. If 2 cables enter a 4&11/16 box with a single gang mud ring, that's 4 circuits down right there.

Most of the home runs won't reach but for the ones that do I like the 4-11/16 idea. Thanks

 

[wireman71]

I'd re-use them for sure and pass the savings on to the customer. I've seen knob and tube that is serviceable. Something wired in the 80's is fine. Now if you're charging for homeruns but not putting them in that's another matter..

 

[stickboy1375]

I'd re-use them for sure and pass the savings on to the customer.

Look at the bright side, it's already been tested... I try like hell to reuse existing feeders in any type of remodel work...

 

[Pierre C Belarge]

I'd re-use them for sure and pass the savings on to the customer. I've seen knob and tube that is serviceable. Something wired in the 80's is fine. Now if you're charging for homeruns but not putting them in that's another matter..

By visually looking at any conductor, but mostly older conductors, how do you verify that the conductor insulation is suitable and free from treeing and other issues that affect the integrity of the insulation.

Sometimes Knob & Tube may look just fine, but is most likely past it's useful life expectancy. The same could be said for other conductor types as well. Maybe during the time-line before you came on the job there may have been a fault in the circuit, maybe a person trying to reset the breaker after the fault...Hmmm I wonder what that does to the insulation of conductors???