Using SmartThings as a alarm system


I’d like to set up my SmartThings system as an Alarm System. I appreciate it is not an ideal system but I’d like to see where I can go with it. I have a number of motion sensors, multi sensors and presence sensors which will work for my system, but I’m struggling putting it all together.

I have the various items set up, and assigned to rooms in the house, but not sure where to go from there. I find the SmartThings eco system confusing and there is no clear starting points - anyone else find this? Or if you can recommend where to start from that would be much appreiciated?

I also struggled to find an external siren/alarm which I could use with Smartthings. If the system is triggered, ideally there is an external siren and visual deterrent.

I’d like this to be intially a basic system - and then to build from there. (ie, when no one at home set the alarm, turn off alarm when we arrive home, and arm certain areas of the house at night time - windows and external doors for example). In future, I feel I can grow it out.

Any tips on where to start and how to go through with this would be great and would be muchly appreciated


External sirens require a special permit in most cities, so that’s why they are not a common item to find for sale.

With “plain old SmartThings”, you can easily turn on any set of lights, though, and that may likely be a sufficient deterrent in most cases. Internally … just Google “z-wave siren” and a few good choices will appear.

The main shortfall with SmartThings for security is that the built-in SmartApp “Smart Home Monitor” (SHM) doesn’t have a lot of options. No “safe zones” for use while the house is occupied at night, for example; but the worst? No exit and entry delays to permit you to arm and disarm the system without setting it off. (SHM is meant to be armed and disarmed externally using presence sensors, your phone, the app, or an app tied to your door lock code, perhaps).

Both of these issues can be addressed by using alternative SmartApps like Smart Alarm (no longer supported by devs, but I think it still works).

I wouldn’t suggest a siren outside, even if you could find one. False alarms will make you tthe neighborhood pariah in a hurry. Unfortunately, false alarms can be common, especially when you have a device with a failing battery (or if you use the sensors that ST produces). Presence detection doesn’t always work immediately either.


You can use any 12V DC outdoor or indoor alarm siren coupled with a power adapter and a Z-Wave or Zigbee switch.


External sirens are common in rural areas, but not urban ones. They are quite popular in various parts of the UK.

Assuming you live in an area that allows them, there are two that work easily with SmartThings, the Fortrezz outdoor siren and the popp outdoor siren. UnFortunately, the Fortrezz outdoor model has become hard to find. The popp is widely available, but is expensive. It does have some nice features, though.

You can find discussion of these in the following thread:

Or as @geko suggested, you can just use it mains powered siren and and use a relay to control it.

As far as what to do next, assuming that you are OK with the various reliability issues and dependence on the Internet, you might as well just start with the official smart home monitor feature and see how far that gets you.

You might also find the following of interest: