Ceiling between ground floor and first floor has sagged/leveling

Good day dear forum,

My wife and I have bought a semi-detached house from 1929. Now I have removed a lot and found that the floor on the first floor is about 4 cm lower at the lowest point. The ceiling is a wooden ceiling.

Currently, there are still chipboards on the floor.

Now I want to level the floor in order to subsequently lay tiles or parquet.

I am currently unsure how to best approach this.

One option I have is to fill the floor with leveling compound. The disadvantage is that I put a lot of weight on it, the amount of leveling compound is of course very expensive, and also that the brittleness is quite high.

Another option I see is to remove the chipboards, apply a leveling screed, and then lay dry screed panels. The disadvantage here is the somewhat higher floor build-up in the already low room. Also, I do not yet know how load-bearing the area between the wooden beams is.

Now to my question: Do you know of any other alternatives or how would you do it?

Thank you in advance for your opinions and suggestions.

So first you should clarify why it has sagged like that! It sounds as if the wooden beams are sagging. That would be a bit strange!

A good option for such an adjustment is otherwise:

Remove chipboards etc., then bring tongue and groove boards (should be about 4cm thick) to the side of the beams and screw them into the beams. Then lay OSB on top and then you can lay your floor. For tiles, it must be noted that you have to be very careful. Otherwise they will crack AND if you ever want to remove the tiles, that is not really fun.

Hello

Watch this video, everything is explained there.
([MEDIA=YouTube]rKnJScDIM-E[/MEDIA])

Regards

Good evening, thank you in advance for the answers.

The current status of the project is as follows:

The extension in [Haolrahmenbauweise] is up and sealed. The gutting is complete and the electrical wiring as well as the heating pipes are mostly installed. I am progressing more slowly than expected, but this is due to a professional change.

So now the construction of the house can begin.

The question posed above is still relevant. Based on your answers, I have decided to follow the tip about attaching boards on the sides to level the floor. Many thanks for that.

However, two questions have come up again, which I keep reading about but are rarely sufficiently answered.

First, there is the question of whether the space between the beams can or should be filled with loose fill. If yes, are the inserted boards sufficiently load-bearing to hold the additional fill without it coming out again on the ground floor? Or is the weight of the screed boards, occupants, furniture etc. distributed onto the screwed slats so that the fill is minimally loaded downward?

The second question I have is regarding impact sound insulation. If I lay the dry screed boards on the slats, does the impact sound not also transfer to the wooden beams and thus to the rest of the house? Should one rather use screed boards with a lower layer of wood fiber, mineral wool, or foam plastic?

Again, many thanks for your answers.

If the structural engineering is correct, 4cm deeper in one spot is sometimes character and not a mistake. Furniture can also be adjusted. Impact noise means decoupling. If you are unlucky and the beams transfer sound wonderfully, it simply remains loud.

I would prefer to fill the spaces between the beams with mineral wool, which is also better suited as sound insulation. The most important questions when constructing the floor are: what does the room height in the upper floor allow AND: what do load capacity and budget allow.

If nothing is limited, you can go for the full program with OSB boards on the beams, then screed insulation and heated screed, thus creating a high-quality, decoupled, 100% level subfloor.

If that is not possible, it is better to install the impact sound insulation between the OSB board and, for example, a floating laminate floor. Tiles on sagging and therefore moving wooden beam ceilings are a topic of their own; no idea if multilayer fabric reinforcement is enough to bridge cracks.