Placing sensors

I am just starting my install and was wondering if anyone had any tips on placement of motion sensors specifically to trigger lights when entering a room.

I have two doors on either wall of a corner, one is a bedroom and the other the washroom. I initially thought I could a sensor on the ceiling above each door, but I believe they would both trigger regardless which room I was entering. For the bedroom I only want it to trigger when entering, not for all movement. The door is open so I can’t choose a door sensor. The bathroom I’ll have on a 5 minute timer, but I still don’t want to trip it when I’m walking into the bedroom.

Any ideas or suggestion are welcome. Thank you.

This is always challenging. Sometimes you just have to use trial and error.

I have a sensor facing up on a shelf inside a bento box. You can walk past it all day long and it won’t trigger unless you wave a hand over it (which is what I wanted).

I assume your two doors are 90 degrees to each other?

A lot of people will use masking tape to narrow the field of a motion sensor. If you mask the left side of the one on the right and the right side of the one on the left you may be able to get a trigger point limited to one entry.

You can also do like I did with the bento box: put the sensor on the ceiling, but inside a box or dummy fixture pointing down. This can really narrow the field.

Another option for the bathroom if the door opens in is to put the sensor inside the room behind the door. This will catch the motion of the door from the other side and turn on the light before the door is all the way open.

If you’re willing to set up more devices, you can also use zone detection so each room is controlled by multiple sensors. This can solve the overlapping view problem by paradoxically making the area viewed large enough that the overlap isn’t enough to trigger the other room.but this does require multiple sensors for each room.

@bravenel , @johnconstantelo and others who do a lot with motion sensors may have more ideas.

1 Like

Thanks for the tips! I’ve been reading the forums here lately and appreciate all your input for both this and other topics!

I will do some trial and error with them as soon as I can, for now I’m just buying parts of the system and waiting for the imminent release of Hub 2. So far I have 7 GE Links, 3 Hue, a Tap, Sonos Play 3 and two Peq motion sensors, which I plan to order more of and their door sensors this weekend to prepare for Hub 2 to drop.

I really like the box idea for certain specific elements of the setup too!

1 Like

As long as you mount it flush against the inside of the wall where the door is, and a couple of feet to the side of the door if possible and as high as possible, it won’t see outside the doorway, but it will detect anyone crossing the threshold. This kind of sensor may not work for keeping the lights on in the room, and a second sensor may be needed for that – depends on the room.

The angle of sensitivity is fairly wide with most motion sensors, so another good option is to mount as above, but tilt it inward toward the inside of the room, so that the doorway threshold becomes something on the edge of the sensitivity range. That way you still get the threshold effect, but see more of the room.


Flush against the wall but at right angles to the wall, so the sensor points parallel to the wall with the door.


And this is how I fine tune my SmartSense Motion Sensors when I mount them. I can bend the paper clip for both left/right and up/down. The paper clip slips into the screw mount hole on the back of the sensor. The white hangar is 3M Command small hook. Once mounted, this cannot be seen, so while it’s funky, it works very well and is simple to install or remove.


Thats so cool!!! Love the ingenuity Bruce!

I’m stealing @bravenel’s idea… I do wish the mounting plate that came with ST/PEQ’s sensors provided some sort of adjustment.

The advice Bruce gave is pretty much what I do. Coverage with the ST/PEQ sensors is really decent, and what I also do is try to cover as much of the room as possible while avoiding a direct line of sight to windows. I did that once, and the motion sensor literally stayed active until it ran out of battery power in a few hours.

I’m going to experiment with one on a ceiling near a door into a room to see how that goes, as well as a couple down a long hallway.

I also use command strips instead of the super-glue-like adhesive strips that come with the sensors. Those things will do some damage if you plan on removing the sensor some day.

1 Like

I think @bravenel might have mentioned doors but I would avoid anywhere near metal or doors with large glass areas and windows. These areas tend to be closer to outdoor temperatures than a wall in the middle of the room. Also don’t mount too high or low, chair height to head height while standing would be ideal. Best would probably sitting on a table really.

1 Like