Est. 1998 — 27 years of woodworking knowledge
OT-Find Junction Box Inside Wall
howard gorman
I need to locate a junction box that is behind drywall. Something that can "see" inside the wall. I know there are reasonably priced scopes for this and I've heard of the Walabot, but it doesn't work on iPhones. Any suggestions would be greatly appreciated, I don't think a simple magnet type device will be strong enough. Thanks
How do you know it is there at all?
John in New Mexico
Junction boxes are not supposed to be covered up like that, so if the wiring was professionally done there won't be any hidden boxes. Of course, it does happen.
I would go with a magnet if it's a metal box. If you know its there, you must know what it is made of?
Re: OT-Find Junction Box Inside Wall
Don Stephan
A well equipped electrician may have a scanner that can follow energized electric wires behind drywall. But even that might not be definitive.
Re: OT-Find Junction Box Inside Wall
Bill Howatt
I've never hard of Walabot so I looked at their site and they do have a model for iPhones. Bit pricy for a one-time use though but I imagine you may well find further use for it.
Shouldn't be too hard to find an old Android phone dirt cheap for use with it. Don't need any of the telephoning stuff just the "computer".
Bill
Re: OT-Find Junction Box Inside Wall
Dave Bair
A magnetic compass (not the circle-making kind) might get you there.
Re: How do you know it is there at all?
Don Stephan
Does anyone know when plastic boxes and plastic covers were first made? If the drywall cover is older than that a magnet is likely, if after that date a box and cover behind the drywall might be metal or plastic.
Re: OT-Find Junction Box Inside Wall
John K Jordan
The last stud finder I bought from HD will also detect and trace electrical wiring.
Re: OT-Find Junction Box Inside Wall
al morgan
USB endoscope works for me....less than $20, hooks up to phone or laptop, has a light on it. Drill small hole in wall (in a hard to see spot) where you suspect box is, fish around while viewing what it sees on phone or laptop. Look for box, as well as wires. Can be somewhat tedious, but puts eyes where you need it. If wall is insulated, then this mitigates the usefullness of it, but still it can be done.
Also a electrical fishing tape can be used to feel around for the box.
Re: How do you know it is there at all?
Mark Nowicki
Could be that he forgot where he put it. 
Re: OT-Find Junction Box Inside Wall
Mark Nowicki
https://www.homedepot.com/p/RIDGID-Micro-CA25-Inspection-Camera-40043/203258908
Re: How do you know it is there at all?
John in New Mexico
I have seen drywallers hang sheets over the boxes and then cut them out afterwards. That time I fortunately remembered where they were because they had forgotten to cut a couple out It was a bit of a pain to fix that, but then those guys were paid by the sq foot rather than hourly so I didn't really blame them for working the way they did. If paid hourly the owner could have said "go back and fix that on your own time."
Re: OT-Find Junction Box Inside Wall
howard gorman
Thanks Mark I just ordered it.
Re: OT-Find Junction Box Inside Wall
Mark Nowicki
I have the Milwaukee model, one of my more useful purchases.
You will not regret it.
Re: OT-Find Junction Box Inside Wall
Jay Lombardo
It depends on if the house is piped in TW conduit or house is run in romex. If it's conduit tape up the end of your fish tape and push it into the pipe until it stops and listen for the banging in the hidden box. You can generally determine a spot between point a and point b by pushing from different directions and how for the tape goes in. I have had to find many hundreds of buried boxes in 50 Years of electrical work. Believe me it is way, way more common than people here want to believe. If you are dealing with romex you will need a camera and a series of guesses 
. Everything around here is required to be in conduit, no romex.
Good luck
Re: OT-Find Junction Box Inside Wall
Jay Lombardo
It depends on if the house is piped in TW conduit or house is run in romex. If it's conduit tape up the end of your fish tape and push it into the pipe until it stops and listen for the banging in the hidden box. You can generally determine a spot between point a and point b by pushing from different directions and how for the tape goes in. I have had to find many hundreds of buried boxes in 50 Years of electrical work. Believe me it is way, way more common than people here want to believe. If you are dealing with romex you will need a camera and a series of guesses . Everything around here is required to be in conduit, no romex.
Good luck