At first, being able to switch home lights on and off from a phone was fun. Later, even taking out the phone and finding the app became an inconvenience.
One of the smart-home devices I have kept using the longest is not an elaborate touchscreen. It is a small button by the front door. One press turns off all the lights, two presses turn on the living-room light, and a long press starts the robot vacuum.
It was not always this simple. I once tried to make sensors decide entirely on their own when the family was arriving home or leaving. The result taught me a memorable lesson.
I changed the switches, not the lights
I wanted smart lighting throughout much of the home, but replacing every light fixture seemed unnecessary. There was no reason to discard functioning fixtures, and I wanted to preserve the familiar act of pressing a wall switch.
I chose compatible Zigbee smart switches. The lights themselves stayed in place while the switches brought their power control into SmartThings Station.
The advantage was that everyday use did not change. Nobody in the family needed to install another app or learn a new method for switching on a light. Smart-home features were added to the familiar routine.
But a smart switch is not merely a decorative accessory. Domestic electrical wiring differs in neutral conductors, lighting loads, switch circuits, and other details. Check device-specific installation requirements and entrust electrical work to qualified professionals. This account describes my experience, not instructions for rewiring a home.
One button was enough when leaving
Once the switches were connected to SmartThings, I could control several lights together.
I installed a smart button near the entrance. The first action I configured was turning off every light with one press. I no longer needed to walk through each room checking what had been left on before going out.
I later added a double press to turn on the living-room light and a long press to start the robot vacuum.
| Button gesture | Action | Typical situation |
|---|---|---|
| Single press | Turn off all lights | Just before leaving |
| Double press | Turn on living-room light | Arriving home and needing light |
| Long press | Start robot vacuum | When I want cleaning to begin |
These are hardly spectacular technical features. But after using a smart home for several years, I learned that the most frequently used actions should need no explanation.
I initially wanted the house to infer arrivals and departures
As the button became convenient, I wondered if it would be even better to eliminate the button press.
I tried routines that turned on the living-room light when the front door opened late at night, and started the vacuum when a door-lock event occurred around the morning commute. It seemed logical during setup.
It did not last. Family members woke up and went out at different times. When one person left, others could still be home. An event from the front door did not tell me enough about the situation inside.
So I added sensors: an open/close sensor on the interior door by the entrance, and a motion sensor to detect movement. I hoped that the order of the events could distinguish arrival from departure.
On paper, this looked like a reasonable algorithm. A few times it worked exactly as intended. The difference was that working a few times is not the same as being reliable every day.
Sensors could see movement but not the family's intentions
The family did not follow the paths drawn on the diagram. Sometimes someone opened a door and came back inside. Sometimes sensors recorded the events in a different sequence. And doors open for reasons other than arriving or departing.
The most frustrating case occurred when one family member left and the automation switched off every light. The system had executed the conditions I wrote perfectly, but another family member was still inside.
For the person leaving, switching off the lights might feel natural. For the person remaining, the room suddenly went dark for no apparent reason. I had added sensors to make the house smarter, but instead created a feature that interrupted family life.
A sensor can detect a door opening and a person moving. It cannot tell who left, whether the house is completely empty, or whether the lights should now be off. More time conditions and more sensors did not close that gap.
In the end, I kept the double press
After living with the routines, I removed some of the arrival/departure prediction and kept the entrance button.
The current method is simpler. If I know I want light in the living room, I double-press the button. If the last person is leaving the home, they can deliberately use the single-press all-off function. For actions that affect other people, a deliberate command that works at the right moment is often better than an automatic guess that is only convenient when it is correct.
I felt more relief about the reduction in mistakes than regret about abandoning full automation. The solution had not required buying another sensor.
The standard that remained in our home
Automation should help people. If people have to live according to an automation's rules, the relationship between the tool and its purpose has been reversed.
Switching a light on or off does not always require sophisticated inference. Sometimes a button is enough. Continuously changing measurements such as temperature, on the other hand, may be better suited to sensor-based control.
Let the system decide some things, and leave other decisions to people. After several failed experiments, that balance became my preferred approach to a smart home.
In the next article, I will describe a case where a sensor really was useful: controlling an aquarium cooler using the indoor temperature already reported by our air conditioner.