Combination of tiles and parquet

Thank you for your input! :)

So for me, the currently best fitting option looks like this:

[*]Carefully remove the old tiles (and skirting boards) with a rotary hammer and tile chisel.
[*]Remove the remaining tile adhesive with a diamond grinder.
[*]Sand the screed down so that in the end the new parquet and adhesive reach the same height as the tiles that will remain, so there is no step. Since wrote that the underfloor heating pipes must be at least 40mm below the screed surface, sanding the screed should not be a problem.
[*]Glue the parquet with appropriate adhesive.
[*]Done :)

What do you think? :)

Thanks & best regards, Patrick

...Grind the screed down so far that ultimately the new parquet+glue will reach the same height as the tiles that will remain, so there is no step. Since wrote that the underfloor heating pipes must be at least 40mm below the screed surface, grinding the screed should not be a problem....
What do you think about that? :)

As already written before, a good parquet layer will be able to slowly level that out over the area. Although this will create a slight slope, it is usually okay.

I would under no circumstances grind away the screed. Your diamond grinder probably wouldn’t quite cope with that either, as it is intended for softer materials like glue or plaster.

:
A problem that very often arises in public forums is that absolutely everyone, whether equipped with expertise or not, can represent and post their opinion.
The result is often confusion and helplessness due to conflicting views.
I also suggest to you at this point to primarily consider those statements (also on the topic in question here) whose authors stand out because they also professionally know the field.
Assumptions and "home remedies" are of little help.
In this respect, I may also point out that I hardly believe that you yourself have a grinding technique with a diamond blade. However, these are frequently used by specialized companies.
Moreover, you certainly will not be able to remove adhesives or elastoplastic construction auxiliary materials with that. But if the surface of mineral screeds or ceramic tiles must be ground down by a few millimeters, then you can.
Anyone who has no idea about the matter should not go public with a lack of expertise. And should not confuse the questioner(s) because of that!
It is true that when removing a screed in residential construction (by grinding) you must know exactly what you are doing. That does not correspond to the rules of the trade, that is correct, but here we are talking about "building on existing structures". And that is another league in which we are "playing".
The regulations all refer to the ideal condition. We will rarely encounter that in existing buildings.
Therefore, the height offset of screeds in adjacent rooms is not a "standard-compliant condition." But that is exactly what we encounter — and can either accept the step, the height offset in the walking level, or eliminate it.
It cannot be "prayed away," so we must either remove one side mechanically or build up the other. Due to existing transition points, however, that is not always possible.
So the removal by grinding with a diamond blade remains.
The certainty that the load-bearing capacity is nevertheless not to be doubted results from the nominal thicknesses (in screed installation), which provide corresponding limit values as additional thickness.
--------------------
Regards: KlaRa