Light you never have to switch on
An ordinary home: in the evening you walk from room to room flicking switches. The brightness is always the same — at noon and at midnight alike. At night, on your way to the kitchen, you turn on the same harsh light that hits you straight in the eyes.
In one of our country house projects we did it differently: the home knows what time of day it is and behaves accordingly.
How it works
The day is split into three modes — Day, Evening and Night. Transitions happen automatically on a schedule, and the switching points can be tied to astronomical time (sunset and sunrise are calculated for your latitude — evening comes earlier in winter, later in summer) or to a light sensor on the facade.
The key point: a mode changes the behaviour of every single light fixture, not just "all lights at once". A real example from the project — a bathroom:
- Day — ceiling spots and niche lighting both on: maximum light
- Evening — spots only: calmer, no excess brightness
- Night — spots off, only the niche glows: a soft nightlight that never wakes you up
And so on — in every room. The same switch turns on different light depending on the time of day. You press the same button you always did — the home decides what exactly to light up.
Motion sensors — without the flashbang effect
In hallways and bathrooms, light comes on via motion sensors — following the current mode's rules. At night a sensor turns on the nightlight, not full brightness. The light doesn't cut out instantly either: it fades after a configured delay (five minutes after the last movement in this project), so the system never "blinks" at you for sitting still with a book.
What if you want manual control?
Every zone has a manual mode: if the owner sets the light the way they want it, the home records that and stops interfering — until the mode is reset. Manual control takes priority.
What it changes day to day
- In the evening the home dims itself — easier to unwind
- A midnight trip to the kitchen no longer starts with light punching you in the eyes
- Leaving the house, you never check the switches — modes and sensors turn everything off
- Guests use the home like any other: the switches are where they expect and work as expected
The technical side
The system is built on the wired KNX bus with an MQTT controller running the scenario logic on top. Importantly, the controller is a layer above KNX — not the only brain. Basic light control lives on the bus itself, so even if the controller fails, the switches keep working and the home is never left in the dark.
Scenarios live locally, not in a cloud — schedules and sensors keep working without internet. The behaviour of every fixture in every scene is defined in configuration: "re-tuning the evening" is a parameter change the owner can make through the web interface, without calling us.