Lay parquet flooring from the hallway into the room

If you want to lay the parquet at all costs, at least the screed should be stapled: Cut about 4 cm deep across the joint into the screed with the angle grinder. Under no circumstances go deeper, as you could hit the underfloor heating. It is best to use the guard of the angle grinder as a depth stop. Then insert screed clamps and pour in resin. There is no guarantee that it will hold, but it at least improves the chances.

Apart from that, I still see the difficulty of practically implementing the whole thing if there is little experience so far. I would still start at the cabinet. From there, you are very quickly at the door and have only laid a few layers. Starting from above it becomes much more difficult, especially if you are not a professional. I estimate the entire width of the house at about 10 meters. A few millimeters that are not absolutely plumb at the beginning already amount to noticeable centimeters after the 10 meters.

My problem/question now is, where do I best start laying it? In the hallway or in the room?

Oh yes, do you want to lay it as drawn? That is, crosswise. Then forget it. You will never manage that. Click parquet is usually laid from left to right or from top to bottom. So in your drawing, you would start in the children's room at the top left and at the same time also in the bedroom at the top left. Hoping that when you get to the door in the children's room and also finish the hallway, you will hit the parquet in the bedroom down to the millimeter. It should be easier for a layman to start at the bottom left in the children's room and then lay it parallel to the left wall. That's how I would do it if I really wanted to lay it continuously.

If you want to lay the parquet at any cost, at least the screed should be stapled: Use the angle grinder to cut about 4 cm deep across the joint into the screed. Under no circumstances go deeper, as you could otherwise hit the underfloor heating. It is best to use the angle grinder's guard as a depth stop. Then insert screed staples and pour resin. There is no guarantee that it will hold, but it at least improves the chances.

This is generally how you get the problem under control. It was done exactly like this for me.

Oh yes, do you want to lay it as shown? So sideways.

Then forget it. You will never manage that.

Click flooring is usually laid from left to right or from top to bottom. So in your drawing, you would start in the children’s room at the top left and at the same time also in the bedroom at the top left. Hoping that when you reach the door in the children’s room and also finish the hallway, you will hit the flooring in the bedroom exactly to the millimeter.

It should be easier for the layman to start at the bottom left in the children’s room and then lay it parallel to the left wall. That’s how I would do it if I absolutely wanted to lay it continuously.

I totally agree. To avoid the problem, I would also have started at the bottom by the cupboard in the children’s room. Of course, it would be easier to lay it parallel to the left wall. The problem is: the room then looks long. Since it is longer than it is wide anyway, I would generally prefer to lay it sideways, but not continuously over three rooms.

Moreover, there is the difficulty that when gluing, I can correct much less and for each section treated with glue, I only have a very short amount of time. This is not for the hobby craftsman if you want it in this form.

Hello questioner.
That is quite bold, wanting to start your installation career immediately with a full-surface gluing of multi-layer parquet without the appropriate knowledge.
Let me put it in a more understandable way:
If you master the topics of subfloor preparation and the handling of an adhesive that can only be processed within a certain timeframe after application, then parquet installation as a DIY process could work out.
You should also be familiar with the issue of "wear of the notched trowel" due to abrasion.
Why do I write this at the beginning?
Because in my professional activity I have had to assess damage cases on screeds and floors, including parquet, in residential buildings, where the expertise of the installer/handler had to be legitimately questioned.
As another respondent (BBaumeister) already explained, there is a lot to consider.
For example, that the walls are neither exactly perpendicular to each other nor can it be ruled out that the wall surfaces have the same distances at opposite corners, so the room can be a few centimeters larger or smaller on the left side than on the opposite side.
You should also consider that even with full-surface gluing you leave an expansion gap of at least 5mm. And that (with lengthwise installation, as indicated in the plan) you should preferably reach the side walls of the two children's rooms with half the element width. Only amateurs start laying (here still GLUING, without chance of later correction) and then realize that they end up with 1cm + 0.5cm expansion gap on the side.
The correct procedure would initially be to measure the width of the rooms, divide the room width minus 10mm by the element width, and multiply the decimal value by the element width.
Then you get the strip width you would end up with if the first row of elements was laid without further checking.
For continuous rooms – as far as smaller living spaces like in this case are concerned – no movement joint between the rooms has to be formed. This is made during installation - and not cut afterward. This led to “botched jobs times ten”.
Snap a chalk line through the children’s rooms, hallway, and bedroom to be able to transfer the result of the width measurement (of the elements) to the other rooms and at the same time obtain a straight installation line.
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If after these justified remarks you still have pure desire for a self-installation, I wish you much success!!
Regards: KlaRa

Start in the corner where very likely nothing will be placed. Arrange the joint so that it leads to the window in a way that it does not stand out, that is, towards the brightest window.