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Extending Wires from J-Box

Healdsburg's picture

I started to replace an old bathroom light fixture with a new one of about the same size but discovered that the j-box behind the old fixture is offset and my new one requires a j-box located in the center of the rear of the fixture (see attached images).  Any advice on how to extend the wires over from the old locatoin to the new one is greatly appreciated.  In the past I've used polyolefin heat shrink tubing to remedy this kind of problem with machine wiring.  Is this allowed with residential wiring or is it a clear code violation?  Do I care?  Is there another solution short of opening up the wall?  At this point, the wires in the wall don't see to want to come out any farther.

no images... (post #215041, reply #1 of 7)

Regardless, you can't have a hidden junction box. From where do the wires originate (switch box? from accessible point below in basement or above in attic?)

Not hidden (post #215041, reply #4 of 7)

Covering a box with a fixture is not the same as hiding it.

There are "old work" boxes (post #215041, reply #2 of 7)

There are "old work" boxes that permit installation without having to "open up" the wall -- you'd just have to have enough slack in the cable to reach the new box.  You would:

  1. Cut out the wallboard to fit the new box
  2. Somehow pry loose the old box and disconnect it from the cable.  If complete removal is difficult then let it fall behind the wall.
  3. Notch the stud to clear the new box (for this reason the new box should be as shallow as possible)
  4. Fish the wire into the new box
  5. Install the new box

But if the cable won't reach you have a problem.

More specific advice would be possible if you can get the pictures posted.  It's possible, just takes standing on your head and whistling Dixie backwards.


Of all the preposterous assumptions of humanity over humanity, nothing exceeds most of the criticisms made on the habits of the poor by the well-housed, well-warmed, and well-fed.  --Herman Melville

Are there wire clamps in the (post #215041, reply #3 of 7)

Are there wire clamps in the box that are preventing the wire from coming out farther?

Inside the fixture. (post #215041, reply #5 of 7)

If the mounting plate for the new fixture covers the existing J-box, just punch a hole over the J-box pull the wires into the fixtrue and make a splice there. Mount the mounting plate to the wall and not the box. I've done this too many times to count. 

You could also go into the (post #215041, reply #6 of 7)

You could also go into the attic, locate the wire, cut it off and make a connection in a J box there then pull wire to the new location.

Florida Licensed Building Contractor, 50 years experience in commercial remodeling, new homes, home remodeling and repairs and all types building maintenance.

right, of course (post #215041, reply #7 of 7)

I was reading him to mean that he was needing to move the fixture and the old junction box would not be behind the new fixture location, rather than the the fixture was covering both the old box and  a new box.

I see now what he meant.