Temporarily repair Rigips ceiling - plastic sheeting? Alternatives?

Hello everyone,

we have the problem in our temporary home that we currently have a "crumbly ceiling" in the bathroom. We want to spend as little money as possible on it, but the current state is very annoying at the moment. The problem is that before we moved in, there was water damage where water from the upper bathroom seeped into the ceiling. The water in the bathroom above has since been turned off and is no longer wet. We treated slight mold formation in the corners of the room with the appropriate agent, which is now dead and/or gone.

However, we have the problem that after every shower, the old white paint layer flakes off from the ceiling. Always small pieces / flakes. I assume this is due to the old water damage that has dried out + the paint is probably extremely old and was not valuable. Now I don't want to put new panels on or invest much money, as we will only be here for a few more months.

Who can give us a tip on how to stop the bathroom ceiling paint from crumbling into my contact lens case? :D Is there some kind of foil that I can just stick over it on a large scale that will cover us for half a year? Alternative ideas? I’m thinking pretty “after me, the flood” because I strongly assume whoever buys the house will have to renovate all bathrooms anyway.

Best regards Kati

Would go over it once with sandpaper and touch up with cheap wall paint..

Alternatively, screw plasterboard panels over it.

I would go over it once with sandpaper and repaint with cheap wall paint..

Alternatively, screw plasterboard over it.

I even have a little wall paint left here. Do you think it will hold then?

Before sanding, I would rather keep my distance because I'm dreading the mess. Also, I'm not sure if there might still be mold spores lurking somewhere, and I'm currently pregnant. I would prefer to "seal" it up there instead of bringing it down into the air. But maybe that's also a misconception.

I would go over it once with sandpaper and repaint it with cheap wall paint.. Alternatively, screw plasterboard over it.

Tape off the bathroom completely beforehand, sand off the old paint, paint the edges, and then "Roll it on, give it to him." Show me the ceiling, the spots...

Alternatively, screw plasterboard over it.

I just had a look – the idea with the boards isn't so bad, they really cost almost nothing. It doesn't have to look nice either. I would only want to do that in the two crumbly corners above the shower and above the toilet. Where there was no water problem before, nothing is crumbling either. So you would only need two. But I have concerns about screwing into the ceiling. Pipes run there, and I have no idea where.

Tape off the area completely beforehand, sand off the old paint, paint the edges, and then "roller, go for it".
Show me the ceiling, the spots...

That already sounds like more work than I want to burden my husband with. I can hardly help him physically right now, and he’s not much of a handyman either. I’m really looking for a quick botched job solution that can be done on a Sunday in 2 hours.
We’re only here for a few more months, and I assume our successors will redo everything anyway; there’s nothing to save in the bathrooms.
I’ll take a photo in a moment, but it’s nothing nice to look at. :D