KNX is an open, wired standard with devices from more than 500 manufacturers, designed for new builds and buildings. Loxone is a single-manufacturer system with a central server that integrates everything. Shelly consists of modules, mostly WiFi, added to an existing installation without building work. The choice depends on the building work, the budget and what you want to automate.
The three systems in a few words
| System | What it is | How it is installed | Best suited to |
|---|---|---|---|
| KNX | An open international standard: a common language spoken by devices from many manufacturers | With its own bus cable running through the property | New builds, full refurbishments and buildings. |
| Loxone | A complete system from a single manufacturer, with a central server called the Miniserver | Wired (Tree) or wireless (Air), always around the Miniserver | Homes and businesses wanting everything in one app. |
| Shelly | Small modules fitted behind switches or in the consumer unit | On the existing electrical installation, almost always over WiFi | Finished homes, rentals and tight budgets. |
Point-by-point comparison
Cost is indicative and relative between the three: it depends heavily on the size of the installation and on what is automated. We give no figures because they change with every project.
| Aspect | KNX | Loxone | Shelly |
|---|---|---|---|
| Who makes it | More than 500 manufacturers, with over 8,000 certified products | A single manufacturer | A single manufacturer |
| How devices communicate | Bus cable; also radio and IP | Tree bus or Air radio, both Loxone’s own | Mostly WiFi; also Bluetooth, Zigbee, Z-Wave, Matter and network cable on the Pro range |
| Where the intelligence is | Distributed: each device stores its own programming | In the Miniserver, which coordinates everything | In each module; scenes between modules need the home network |
| If one part fails | That part stops working; the rest carries on | If the Miniserver fails, automation stops | If a module fails, only that point; if WiFi fails, scenes and remote control are lost |
| Without internet | Works the same | Works the same; data is stored on the Miniserver | Each module works locally; the cloud is optional |
| Building work needed | Bus cabling: building work or conduits in place | Cabling during building work, or none with Air | None or minimal |
| Who programs it | An integrator using the ETS software | A Loxone partner using Loxone Config | You or an installer, from the app |
| Future expansion | Any KNX product from any brand | Loxone products and, through interfaces, KNX, DALI or Modbus | More Shelly modules; can be integrated with other platforms |
| Relative cost | The highest | Medium to high | The lowest |
KNX: the open standard
KNX has been on the market for more than 30 years and is an international standard (ISO/IEC 14543-3). Its main advantage is that it does not depend on one brand: if a manufacturer disappears or a product is discontinued, another maker’s product replaces it.
- For: manufacturer independence, no central point of failure, a huge product range and a very long service life.
- For: it is the usual system in hotels, offices and buildings, as well as homes.
- Against: it needs its own cabling, so it suits a finished house less well.
- Against: it is the most expensive of the three and requires a trained integrator.
Loxone: everything from one manufacturer
Loxone makes the server, the actuators, the switches, the sensors, the audio and the app. Everything is designed to work together, which simplifies the project and gives a very consistent experience. Data is processed on the Miniserver itself, not in the cloud.
- For: one app for lighting, climate, blinds, audio, access and energy.
- For: a wired version for building work and a wireless version for finished homes.
- For: it connects to other systems through KNX, DALI, Modbus or DMX interfaces.
- Against: you depend on one manufacturer and its partner network.
- Against: the Miniserver is a critical part; it is wise to plan for what happens if it fails.
Shelly: home automation by modules
A Shelly module is fitted behind a switch, in a junction box or in the consumer unit, and makes that point controllable from a phone. You can start with one blind or one light and expand later, without touching the rest of the house.
- For: no building work, low price and the option to proceed in phases.
- For: it measures electricity consumption in great detail.
- For: it works locally and integrates with Home Assistant, Alexa, Google Home or Matter.
- Against: it depends on WiFi quality; with many modules a well-planned network is needed.
- Against: many models need a neutral wire in the switch box.
- Against: it does not offer the variety of switches, sensors and displays of KNX or Loxone.
Which to choose for your case
These are pointers. The final decision is made with the floor plan, the state of the electrical installation and a list of what you want to be able to do.
| Your situation | What we usually recommend |
|---|---|
| New build or full refurbishment | KNX or Loxone, wired. This is the moment to leave the installation prepared. |
| Finished home, with no building work | Shelly, or Loxone Air if you want a more complete system. |
| Tight budget or starting gradually | Shelly, in phases. |
| Rented flat | Shelly: it is installed and removed without leaving a trace. |
| You want one app for everything, with audio | Loxone. |
| Hotel, office or building | KNX. |
| You do not want to depend on one brand for 20 years | KNX. |
| You only want to measure and reduce consumption | Shelly. |
They are not mutually exclusive: they can be combined
Combining makes sense when each system does what it does best. Mixing to save on every item usually ends in an installation that is hard to maintain.
- Loxone has a KNX interface, so a Miniserver can integrate KNX switches or actuators.
- The Shelly Pro and Gen3 ranges can communicate with a KNX installation over IP. A KNX IP gateway is needed on the network and they do not support KNX Secure.
- It is common to leave lighting, blinds and climate on KNX or Loxone and use Shelly to measure consumption or automate secondary circuits.
- A platform such as Home Assistant can bring all three together in one dashboard.
Common mistakes when choosing
- Deciding on the price of the first quote without thinking about maintenance over ten years.
- Choosing a wireless system in a new build, when it is the easiest moment to run cables.
- Filling a house with WiFi modules on a barely adequate home network.
- Not requiring handover of the project: in KNX, the ETS file; in Loxone, the configuration.
- Automating for its own sake, without a list of real needs.
How we approach it
We work with all three systems: we have been KNX Partner no. 11093 since 2006 and are a Loxone partner, and we install Shelly. We have no reason to push you towards one: we propose the one that fits your building work, your budget and what you want to achieve, and explain why.