but picking by a professional is getting more and more expensive...
Experience does not come for free and it’s not just about the picking. The architect doesn’t just give you a drawing and say "here you can build from this," usually they have more to do. Same here, the SI usually has not only the picking as a task but also the parameterization and the commissioning. If they are also a qualified electrical installer, then also the installation itself.
The fact is unfortunately that licensing with KNX is also getting more expensive!
The end devices are getting cheaper for that. Meanwhile we are at about 12 euros per switching channel with a powerful functional and logic package on the software side that not even Shelly can really keep up with anymore.
Personally, it makes my toes curl nowadays when I hear that "Smart Home" with radio is being implemented in a new building and Alexa or Google Home are mentioned at the same time.
The term smart home is simply overused and applied to anything that somehow has to do with remote controls. In the end, more or less true smart homes are in the single-digit percentage range among these. That’s why I, for example, always tend to speak of intelligent buildings as soon as it goes beyond the gimmicks you are talking about here.
For me, that has at most to do with ease of operation (although I will never understand why people tell Alexa what to do instead of just quickly pressing a button).
Hehe, yes, that’s then a smart home, right... TV says so, so it must be true.
I am definitely not completely against radio, but all the limitations (Actuator x can only be had with Z-Z-Wave, Actuator y cannot be integrated into my Smart Home station, Button z must be EnOcean because otherwise batteries have to be replaced...).
Radio works as a supplement. That basically says it all.
That would be all too prone to errors for me and reminds me more of tinkering than a good overall concept. Especially when it really comes to a "smart" home, it gets absolutely wild with radio. That is much more systematic and organized with KNX or other bus systems - but a bit more expensive too (although it really depends on the installer/integrator).
You always have to consider the overall installation. Then it suddenly becomes obvious that radio is not the best thing and often ends up being more expensive. Not to mention all the problems and incompatibilities. As I said, it is useful as a supplement. But as long as the devices in the house need 230V to operate, it is not really complicated to lay a data cable alongside. You just have to remember it beforehand or pay someone who knows what they are doing and has an overview of the possibilities and doesn’t just work by rote.
Radio certainly has its justification. Especially in terms of flexibility...
Surely, for the 2-3 variable things it is indeed practical. But as you wrote yourself, the light switch (in my opinion, though not in every room) will stay where it usually is. Also the sockets and yes, also the stove, dishwasher or heating and other building technology systems. So I see no advantage of radio here. The power cables have to go to the consumers anyway, so why not also the data. A positive side effect is that you eliminate the sometimes necessary batteries and other sources of error.
Well, sure, I can equip everything with motion or presence detectors, but I often have situations in which I don’t want the light to switch on when entering the room, for example. Typically in the children’s room.
Correct, typically the presence detector (if there is one) in the children’s or other bedrooms doesn’t necessarily switch the light on and off all the time. But the lights on the stairs, in the bathrooms or hallways can be fully automatic very well and can do much more than just on/off states without much effort.
But other requirements apply here which are only conditionally applicable to single-family houses.
Sure, different rules apply in single-family houses. But here too there are plenty of recurring processes that can be automated.
Now something concrete instead of generalities. How do you manage so that the roller shutters do not lower and lock you out when you are outside?
One presence detector, two door contacts and a bit of software logic. The processing of variables takes place in the motor itself.
Or to put it differently: why should I spend 10% of the construction costs on smart home?
No, not for the vague "smart home" (whatever you imagine that to be). For the entire electrical trade including building automation.
I would still like to know which applications in smart home make life easier and make sense energetically.
That is always very subjective and cannot be answered clearly. For that reason, it is partly quite expensive because you have to have many preliminary conversations to find out what needs and ideas the person has. Every single-family house is a custom job after all. You find, for example, the lamella tracking annoying. Others want exactly that in their single-family house and possibly other shading variants and options. It’s not like an office where you need certain lighting at certain times and occupational safety requires this and that and the 99% same routines happen every day.