Overview
KNX, in practical terms.
KNX is the protocol for buildings rather than flats. It is wired — a twisted-pair bus running alongside your mains — which means no radio congestion, no batteries, no hub that can fail, and a device lifespan measured in decades rather than product cycles. It is the global standard for commercial buildings, hotels and large villas, and it is vendor-independent: hardware from different manufacturers works together, and you can still buy replacements in ten years.
The catch is that KNX only makes economic sense at one moment — while the wiring is still open. Retrofitting it into a finished building rarely pays, it costs several times a wireless system, and it needs a certified integrator with ETS software rather than an electrician. Below roughly 3,000 sq ft it is usually overkill; Zigbee does the same job for far less. See KNX vs Zigbee in India.
