ᐅ Should the joint between the ceiling drywall and the wall be sealed?

Hello,

My name is Markus, I am 47 years old and work as a locksmith.
We have recently built a new house. We are doing the painting work ourselves. Unfortunately, I filled the joint between the drywall and the plastered wall with filler, which caused significant cracking.
I have now removed the filler and would like to ask for advice on the proper professional method to proceed. The joint is currently 3 to 6 mm (0.1 to 0.2 inches) wide. Thank you in advance for your help.

Regards, Markus

Buy angled corner tape and apply joint compound.

A friend advised me against using Kurt sealing tape; I have seen the ceiling-to-wall joint myself. The tape detaches from the plaster or tears. Does anyone have another suggestion?

I wrote something earlier but was warned for it, no idea why. Allegedly off-topic and without added value, even though it was advice specifically for the original poster. I’ll try again with a rephrased version.

The joint cracked because the plaster behaves differently than the concrete.
So either use a flexible joint (silicone or acrylic), but this is a maintenance joint and needs to be renewed regularly. Or create a reveal joint (keep the joint clean and consistently sized everywhere). Or attach ceiling moldings (on one side).

Since the joint is not particularly small, can I apply and smooth the acrylic now and then proceed with wallpapering? Does it make sense to apply the acrylic in two layers to reduce the risk of cracking?
Thank you very much for your answers.

Mathodo schrieb:

A friend advised me against using Kurt joint tape; I’ve seen the ceiling-to-wall connection myself. The tape detaches from the plaster and/or tears.
Does anyone have another suggestion?

Not applied correctly. If properly filled and finished, it won’t tear. I have over 40 meters (130 feet) installed in my place without any issues. You won’t get a neater finish visually.