Which solution suits your home?

A missing additional light switch, an existing switch in the wrong place, or a modernization pending – many homeowners are familiar with this situation. This often immediately conjures images of walls being chiseled open, new cables, and extensive electrical work.

However, today there are various ways to retrofit light switches and lighting controls – from classic wired installations to professional bus systems like KNX, and even Wi-Fi or wireless solutions.

But which technology is suitable for what? And does an additional light switch always really require laying a new cable?

This overview shows the most important differences.

1. Classic wired light switches

Classic electrical installation has been standard for decades. The switch is directly connected to the lighting via cables and switches it mechanically or electrically.

This solution is still widely used, especially in new builds or core renovations.

Advantages of wired light switches

✅ robust and proven technology
✅ no wireless or network technology necessary
✅ permanently fixed installation
✅ easily plannable for new builds

Disadvantages

❌ additional switches require new cables
❌ interventions in walls or ceilings possible
❌ higher installation effort
❌ later changes often complex

The biggest disadvantage is particularly evident in existing buildings: if an additional switch is to be added later, this often means chiseling work or new cable routes.

2. KNX – the professional smart home bus system

KNX is considered an established standard in the professional smart home and building automation sector. Unlike classic switches, KNX works with a bus system through which various devices communicate with each other.

Lighting, blinds, heating, or scenes can be centrally controlled and automated.

KNX is frequently used in:

• high-quality new builds
• larger residential buildings
• office and commercial properties
• extensive smart home projects

Advantages of KNX

✅ very powerful
✅ extensive automations possible
✅ central control of many functions
✅ professional and established standard
✅ scalable in the long term

Points to consider

❌ higher investment costs
❌ planning usually best done early in the construction process
❌ programming and specialist knowledge required
❌ retrofitting individual functions often more complex

KNX offers enormous possibilities and is excellently suited for comprehensive smart home projects. However, for individual retrofits or additional switching points, the effort is not always the most economical or simplest solution.

3. Wi-Fi-based smart home systems and relays

In recent years, numerous Wi-Fi solutions have established themselves. These include Wi-Fi switches, smart relays, and app-controlled systems – for example, relay solutions like Shelly or similar products.

Control is usually done via:

• smartphone app
• Wi-Fi network
• cloud or local automations
• voice control like Alexa or Google Home

Many of these systems are installed behind existing switches or in flush-mounted boxes.

Advantages of Wi-Fi solutions

✅ app and remote control
✅ voice control possible
✅ automations and schedules
✅ integration of other smart home devices
✅ often usable without central control

Points to consider

❌ stable Wi-Fi is important
❌ setup and configuration depend on the system
❌ partial flush-mounted installation required
❌ network and app issues play a larger role

Wi-Fi systems offer high flexibility and many smart functions. At the same time, the user experience often depends more on the network and the chosen smart home platform.

Those who already use a Wi-Fi-based smart home will often find a suitable solution here.

4. Wireless solutions and battery-free switches

Another option for retrofitting are wireless solutions. The switch communicates wirelessly with a receiver, which performs the actual switching function.

The big advantage: additional switches can often be added much more easily – without having to lay new cables to the switching point.

Battery-free wireless switches are particularly interesting.

Here, the necessary energy is generated directly when the button is pressed. No battery change is required.

Advantages of wireless and battery-free solutions

✅ no cable to the switch necessary
✅ flexible placement
✅ often quick retrofitting
✅ no battery for battery-free systems
✅ extensions usually easy to implement
✅ ideal for additional switching points

Limitations

❌ wireless range depends on environment and construction
❌ separate receiver required depending on the system
❌ differences between manufacturers and technologies

Especially for retrofits or where no new cable route is desired, wireless solutions play to their strengths.

Smart Home: Complete system or modular growth?

A common question is not only which technology is better, but also how extensive the smart home should become.

Some systems rely on complete planning and central infrastructure. Others allow for a modular setup.

Both approaches are valid.

While KNX is often planned early in new builds and Wi-Fi systems offer many app and automation possibilities, many users prefer a gradual expansion.

Typical examples:

• first add an additional light switch
• later integrate blinds
• then add scenes or app control

A modular smart home can help to expand functions as needed, instead of implementing a complete overall system from the start.

Comparison: Cable, KNX, Wi-Fi, or Wireless?

The right solution therefore depends heavily on the building, the desired range of functions, and the installation effort.

Conclusion: Which lighting control is the right one?

There is no one-size-fits-all answer.

Classic wired installations remain sensible, especially in new builds or renovations. KNX convinces with maximum control options in comprehensive smart home projects. Wi-Fi systems offer convenient app and automation functions.

However, if additional switches are to be retrofitted and minimal intervention in the existing installation is desired, wireless solutions are increasingly coming into focus.

Ultimately, the decisive factor is not which technology is generally "the best" – but which solution best suits the building, the budget, and the desired comfort.

👉 Do you want to retrofit light switches without major renovations?
Learn in the article „How the Kinetic Switch works?“, how wireless lighting control can work without batteries and without new cables. Or try your first Kinetic-Switch Set at home.