Recessing a door/window contact sensor

So, I know of three normally recessed door sensors:

Insteon --> Not compatible with ST (normally)
2GIG --> ‘RF’ based so not compatible with ST (normally)
Aeon Labs --> Compatible but CRAZY expensive

Since none of these seems to be a viable option I was wondering if anyone else had gone the route of embedding a door/window contact sensor into a door/frame themselves where appropriate (some fire doors aren’t appropriate to cut into), into the edge of the door and in the door frame.

Any issues with that anyone can think of? Just thinking of ways to make them more discrete/neat?

Depending on what sort of frame/door you have this is doable.

Assuming this is a solid wood door a good set of wood chisels and some patience should get things done.
I’ve been known to put magnets and reed switches into the top of a door and the frame.

If you have a router, it would be relatively easy to make a jig to route a space in the top of the door to put the sensor in laying on it’s side. Since any strong magnet should work with it, I’d get a cheap reed switch wand use the magnet from that. Just make sure the position you plan to install it will trigger the sensor.

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I actually plan to do this next week while I’m on vacation. I installed a schlage lock and need a contact sensor to automate lock and unlock. I will tell you how my experience goes but it doesn’t seem that difficult.

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Thanks guys! Pics FTW!

The problem is the position of the antenna, and how much the signal is blocked by the encasing material. Sensors that are designed to be recessed also move the antenna position so that it is near the most likely airspace.

Typical reed sensors don’t do this, the antenna frequently comes out of the exact side where it will be blocked by being encased.

There could also be heat dispersion issues, one of the reason these devices tend to be more expensive. There actually is a reasonable amount of engineering That has to go into them.

Finally, remember that you will need to be able to get it out again in order to change the battery eventually.

When you first put it in, you can test the signal strength. If it works, keep an eye on it. It may be that you need to keep the battery strength at 50% rather than around the 25% it could operate at if it were not enclosed.

If the signal does work OK, pull it out after about 45 minutes and feel it to see if it’s warm. If it does feel warm to the touch, it may not be safe to operate in the enclosure.

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I wouldn’t call the Aeon Labs sensors “crazy expensive.” I bought two on Amazon for $40 a pop.

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Wooden doors shouldn’t block the signal significantly, given how thin it’s going to be on either side of the sensor after it’s installed. Recessing one one in a metal door with a metal frame might end up acting a bit like a Faraday cage though.

That stuff isn’t very forgiving,

I wouldn’t be concerned with heat build up. With the tiny amount of current these devices draw, overheating will not be an issue.

For easy access I’d suggest putting the transmitter in the top of the door. Size the hole so that it’s a loose fit, and let gravity keep it in place. Years from now when you change devices or move, the hole won’t be seen.

One last thing I failed to mention last night. Most interior doors made in the last 25 years are made mostly of particle board / pressed wood/ whatever it’s called. There will be a little bit of real wood along the edges with the latch and the hinges. Better ones will have wood along the top and bottom too, but many don’t. I would advise against trying to cut into one of these without a router, a jig, and some practice.

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Great point about making gravity your friend! Putting the sensor along the top edge of the door would definitely give you the most options.

This is one of those “all home automation is local” issues. If the doors just a wooden door, and it’s not painted, I agree there’s not likely to be much signal degradation.

If it’s a foam core door, if it’s a composite material door, or if it’s painted with a paint with metallic elements, then there can be additional signal degradation. Weatherstripping around the door can also be a factor.

It just varies a lot. So it’s just something to be aware of.

The same thing with the heat issues. Again, if it’s a foam core door, I would definitely check if you’re getting any heat buildup.

It’s just one of those things to check on, not a hard and fast rule. But whenever you see models that are purpose-built for a particular kind of installation, it’s a clue that there may be some extra issues to consider if you use one of the general purpose models in the same set up. :sunglasses:

I would think an easy test would be to temporarily mount it on the outside of the door and see it the signal is strong enough.

Couldn’t hurt.

These aren’t directional broadcasts though, signal may come through the window, or the door, over the door, through an air leak around the doorbell… It’s not quite the same as encasing it in foamcore.