Box or No Box with Motion Sensor


Active Member
Seems simple enough, but I can't find an answer searching.

Do you install a mud ring in the locations you are mounting motion sensors?

I don't. Usually motion detectors are smaller than a gang so the look better flate on the wall or in a corner.
In my opinion most motions are meant to be installed in a corner to give you full coverage of the room. So a box would not work.
What do you do with the wire? Do you just tack it to the stud and fish it out throught a hole in the drywall?
Mine have been retrofit, not new construction. But yes, fish it out of the wall if needed or hopefully put it right at the ceiling corner and go straight up in the attic through the ceiling.
brotsten said:
What do you do with the wire? Do you just tack it to the stud and fish it out throught a hole in the drywall?
I just finished building a big new house and did all the low voltage myself (with my son's help). I used mud rings for all drops & keypads and left wires (CAT-5E, firewire, security wire, and even speaker wire) securely hanging to a stud, close to the position that I wanted to mount the corresponding sensor. When the sheetrock crew came to do their thing they would poke holes where needed. Once in a while they would bury a wire of mine but they would do that to my electrician also. After they were finished, I tweeked the final position as was needed. The spacklers would clean up any extra holes that I'd make.

I would also suggest keeping your wires considerably longer than you need. Even after the spackling and painting you may find that you still need to move a sensor. Rather then make final cuts I shoved as much wire back into the wall as I could shove without damaging the wire.


basically a j-box without the box . . just a frame to trim sheetrock to . .

.. like these -

concerning pre-wire . .

. . if you want the rockers to pull the wire thru the rock, staple it so it sticks out . . if you want to fish it out later (for future) . . staple it so it doesn't stick out . .

. . worked when I did my house, makes it obvious . .

Pete C
JeffCharger said:
what are mud rings?
They are the open backed boxes that are used for Low Voltage wiring. Makes termination a bit easier than using a conventonal elec. box.


edit: See pete explained it while I was typing :p
The only time I've seen mud-rings used with PIRs is for flush mounted units, usually in the ceiling. The Sentrol 5225FM comes to mind. IIRC DSC makes one or two units that can be flush mounted also.
Depends on the design. If it calls for flush mounted PIR's (for example above doorways, firing down halls and other such similar locations), I always use mud rings. If the design calls for a corner mount PIR, I simply stub out or LOOSELY affix within the wall and take digital pic's to reference location.
Four of the sensors I'm installing are combo PIR+CCTV Cams, that would be a lot of wires just sticking throught the rock.

I was thinking of using a keystone plate to pass the wire through, and mounting the PIR on the Keystone to camo it somewhat.

If it's in a corner, I usually wrap the wire around a nail that protrudes through the plane of the future sheet rock. Similar to what Pete said above.
I have done this both ways. The first way was with a large loop of wire that was twist tied (only with a couple of twists) to a nail on the frame. This way it gave you a large target to be able to find when you poked the hole in the drywall. Once you found any part of the loop, just "tug" on it and it will break loose from the nail. Then just mount the detector on the drywall over the hole.

I also used mud rings in my friends house. Problem is I had to come up with a way of mounting the motion detector on a "blank" wall plate to place over the mud ring which was kind of a pain.