The eight hours you are least protected

During the day someone is home, someone is moving around, someone notices when something is off. The moment you lie down, switch off the light and fall asleep, all of that stops. For the next eight hours nobody is watching the doors and windows, and nobody is going to notice that the balcony door never latched properly.

Most people assume home security means buying a siren. Then they find out that detection was never the problem — judgement was. Door sensors are cheap. Motion sensors are cheap. Between them they detect far more than you actually want to hear about. The hard part is deciding when to speak up and when to stay quiet.

A false alarm at 3am is worse than no alarm

This deserves its own paragraph. Say you put a motion sensor in the living room and arm it before bed. At 3am you get up for a glass of water, the siren goes off, and the whole household is awake. The first time you laugh about it. The second time you frown. The third time, you disable the system.

From that moment your home security is zero — and arguably worse than before you started, because you have already spent the money and already given up. So the first question when designing this is not "how much area can I cover". It is "what does a false alarm cost me". The answer is: it costs you the day you turn it all off.

The fix is simple enough. Stop treating armed as a single state. Awake at home, asleep at home, and out of the house are three genuinely different situations, so make them three modes, each arming a different set of sensors and each reacting differently.

What it actually did overnight

The same table, written out as one real night.

1. 23:40

   You go to bed and the mode switches itself

   The bedroom light has been off for ten minutes and your phone is on the charger, so the system decides you are asleep and moves to the sleeping mode. Every door and window sensor arms, living room and entry motion arms, bedroom and hallway motion stays off. You pressed nothing.

2. 02:15

   You get up for water

   Out of the bedroom, down the hall, into the kitchen. Not one armed sensor sits on that route, so nothing happens. It is the least impressive step here and the single reason the whole setup survives past its first month.

3. 03:52

   The balcony door opens

   The door sensor reports open. The system does two gentle things first: the bedside lamp comes up to 10%, and your phone gets an alert with a snapshot from the balcony camera. The siren has not made a sound.

4. The next 30 seconds

   Your chance to cancel

   You look at the photo in the alert, see that the wind pushed an unlatched door open, and tap cancel. The lamp fades out and it is over. One person woke up, and only briefly.

5. If you do not cancel

   Then it really does sound

   Thirty seconds pass with no response, so the siren sounds, every light in the house comes on and the cameras start recording. That noise is now worth making, because the system already checked that you did not want to wave it away.

6. 07:10

   The mode steps back down

   The bedroom light comes on and you start moving, so the system returns to the awake mode and all indoor motion stops being treated as a trigger. Across the whole night you pressed zero buttons.

What actually differs between the modes

Modes are not there to add complexity. They are there so each sensor only speaks when it should. Treat this table as your configuration checklist.

What you need to have

Home Assistant sorts every device in your home into an entity category. Brand and model do not matter — the category does. Have these and everything in this article is buildable.

One more thing is needed: something that records which mode you are currently in. It is not hardware, just a small three-option selector inside the system. Every rule glances at it before deciding whether to act.

How the whole thing works

There are only three stages: sensors report, a blueprint works out which mode you are in, and only then do things light up or make noise.

Use the ready-made decision, do not build one

The hub ships with a set of tested automation blueprints. Think of a blueprint as a fill-in-the-blanks form: the structure is already built, you supply the content. The one doing the work here is binary_sensor_trigger_things, which exists precisely to say "when this sensor changes, go do these things".

The alerting side goes to entity_state_trigger_notify, which watches one entity's state and pushes a message to your phone whenever it changes — the wording and whether to attach a snapshot are both fields you fill in. Arming on the way out goes to notify_leaving_zone: once your phone leaves the home zone, the mode switches to away by itself and you never have to remember.

Different homes, different settings

Those are sensible defaults. If any of the following describes your home, adjust and save yourself a lot of grief.

Three optional extras

Two blueprints cover the core. These three are additions — take whichever you actually want.

Four things it takes care of

You do not have to set it up — just say it

None of the above needs clicking through by hand. The WOOWTECH hub ships with HA-MCP, so AI can connect straight into your system, build the thing, and then go back and check it really runs.

Prompts you can copy straight out

Each block below can be copied whole with the button on the right. Pick the one closest to what you want — you do not need all of them.

Set up security arming for when I am asleep.
Once the sleeping mode is on, arm every door and window sensor.
If a door opens, raise the bedside lamp first and send an alert to my phone.
Do not arm the bedroom or hallway motion sensors —
I do not want to be woken by my own trip to the bathroom.

Build me sleep-time security arming for the master bedroom.
Use the ready-made blueprints, do not write a pile of custom rules.

Three modes: awake at home, asleep at home, away.
Awake at home triggers nothing and only writes to the log.
Asleep at home arms every door and window sensor plus living room and
entry motion, but not the bedroom or hallway sensors. On a trigger,
raise the bedside lamp to 10%, send me an alert with a camera snapshot,
and give me 30 seconds to cancel. Only if nobody cancels within
30 seconds should the siren sound and the house lights come on.
Away arms everything and sounds the siren immediately, no delay.

Also alert me if any contact sensor has not reported for 24 hours,
since that usually means a flat battery. Leave the gas, smoke and
water leak rules unconditional — they must not be tied to any mode.

Once it is built, test it yourself, confirm it really works,
and then tell me which devices you used.

We have a cat that moves around the living room and dining area at night.
For the sleeping mode, do not use any indoor motion sensor as a trigger.
Keep the door and window sensors only, including the balcony door.
Leave the siren out for now and send alerts only —
I want to watch it for two or three weeks and count the false triggers.

The cancel window in sleeping mode is too short — change it from 30 to 60 seconds.
The bedside lamp at 10% is too dim, make it 25%.
Also change the alert text for the balcony door to say "Balcony door opened".
Leave everything else alone.

There have been five or six false alarms at night over the past fortnight
and I never wrote a single one of them down. Pull every trigger from that period
into one list for me: the time it happened, which sensor it was, and which mode was active.
Then see whether they cluster around a particular hour, or around one sensor.
If one of them stands out, drop that sensor from sleep mode and leave the rest alone.

Common questions