ᐅ Two ceiling lights connected to a single circuit

Yes, the plaster will probably only be about a millimeter thick (around 0.04 inches) – try scraping that off.

Sebastian79 schrieb:
Yes, the plaster might only be about a millimeter thick there – try scraping that off

Why? Here we have about 20mm (0.8 inches) of plaster, similar to the walls.

How is that supposed to work? Why would anyone do something like that?

I’m just going to flat out doubt it.

Sebastian79 schrieb:
How is that supposed to work? Why would anyone do that?
I’ll just boldly doubt it

It’s plastered just like the walls. That’s a common practice. Even my apartments from the 1950s have plaster of this thickness on the ceiling. Maybe it’s only 15mm (0.6 inches).

You can doubt it, but that’s really how it is.

Hold the hose to the ceiling, start plastering, smooth it out.

This is not normal with precast concrete elements – first of all: why? Why would you apply a thick layer of plaster?

And then the how – simply holding a hose against it doesn’t work, because it wouldn’t adhere to the concrete at all. Have you seen this yourself? Have you tried it?

It’s already a hassle even on concrete walls.

It’s definitely not common practice; usually, a thin layer of filler is applied, resulting in a very good ceiling finish.

Well, I’ve seen this myself with our cast ceiling, our interior concrete walls, and our previous house (which had precast concrete slabs). It didn’t look like a struggle. The concrete just needed an appropriate primer (it was quite “sandy”), and there wasn’t much splattering.

Then I noticed the same in five condominiums (built between the 1950s and 1970s) — not how it was done, but the final result.
Also at various neighbors’ places.

I find this quite common here.

That’s why I used the (unprofessional) screwdriver method.