Wallpaper or plaster? Which is better in new construction?

But you first have to have the 15-20,000 EUR to have everything built up by the painter on Q3 with fleece and then painted.

Also always keep in mind:
Painter’s fleece is organic, so is the glue. So is dispersion paint. And it makes the wall more or less airtight.

Not so optimal for the indoor climate.

Yes, that’s true, we don’t have the 15,000-20,000€.
We have max. 5000€ available for the painter.

Isn’t painter’s fleece diffusion-open? And you just have to make sure that the fleece glue is as well? I read somewhere that painter’s fleece is supposed to contribute to a good indoor climate too.

For those who want to push the topic to the extreme, I recommend reading the following: "The Lime Plaster Lie" or searching for it on the web.

Yes, I have already read that cement is often mixed into lime plaster because it is cheaper in production.

I thought so too and that was partly the reason for choosing it. But whether replacing one strip exactly fits in practice, I don’t know.

But: The painter glued my fleece, you can’t undo that. That’s why I can only sand it off and then the whole wall has to be done.

I have read that the fleece wallpaper is stronger/more stable than the glue, so the wallpaper doesn’t tear and you can pull the strip off in one piece (maybe the wrong glue was used? There is special glue for fleece wallpaper).

Yes, painter's fleece is diffusion-open, the adhesive too. Dispersion paints work that way. They used to be completely impermeable, but they are no longer like that. But Mrd is right that all components here have an organic base. That means they are potentially a breeding ground for mold. Mold needs two things: a breeding ground and (frequent or persistent) moisture. If you ventilate and heat sufficiently, this is no longer a problem in a modern new building. If necessary, ask about silicate paint, which is highly alkaline and thus mold-inhibiting. What kind of ventilation concept do you have?

We build KfW55 and do not have controlled residential ventilation (the developer does not offer it). Windows must be ventilated sufficiently. I do want to do something to prevent mold (I don't want to deal with that hassle). I have also already considered silicate paints.

That is not good. Because experience shows that people ventilate too little (twice a day) or incorrectly (tilted window). At least have RegelAir or something similar (window rebate ventilator) installed in the windows. Then you can have decentralized fans installed in the bathrooms (by someone else) to ensure regular air exchange.

This is not good. Because experience shows that people ventilate too little (twice a day) or incorrectly (permanently tilted). At least have RegelAir or something similar (window rebate ventilator) installed in the windows. Then you can have decentralized fans installed in the bathrooms (just by someone else) and thus ensure regular air exchange.

Do you mean that we should have the RegelAir installed afterwards?

We also once asked the builder about controlled residential ventilation or decentralized controlled residential ventilation; he rejected everything.

Are we even allowed to do that within the first 10 years? Could that possibly jeopardize the KFW status?

How do the RegelAir work? Do they ventilate permanently?

How is the construction status?
It is also possible afterwards, but of course more expensive.
RegelAir + exhaust air somewhere in the house (preferably bathroom or kitchen) is the minimum I would do today.
I believe(!) it probably wouldn’t change anything about the Kfw standard, because right now you have window ventilation included in your calculation and that probably has greater transmission heat losses than anything else. If you save that...
Strictly speaking, it should be recalculated.
Yes, it’s like a small protected ventilation slit. But alone it doesn’t bring much, so an exhaust fan somewhere as well (see above).
Better would of course be a decentralized ventilation with heat recovery installed afterwards.
Well, not by the developer, but by a ventilation specialist after handover.
Do you really have a developer (house & land from one source)?