Precast concrete basement - closing joints and spackling

Hello, we have a precast concrete basement. I have now inquired at the hardware store about what I need to close the joints and for the basement living spaces in terms of materials.

The plan now for all joints: a bonding primer on the joints and filling with concrete filler - then sanding the walls.

I will also leave the technical room and storage room as is or just paint over them.

After sanding, I will fully plaster the 3 living rooms with [Rotband Flächenspachtel] and sand them. Do I need to prime beforehand? After plastering, sand again and then paint (without additional primer).

What do you think, does that sound alright?

Hi,

Primer is always recommended for concrete. "Fertigbetonkeller" presumably means that you have so-called semi-precast walls with a cast-in-place concrete core. These have a very smooth surface, so I would advise you not to sand them if you only want to paint them. The texture of the surface will be damaged.

For the rooms you want to fully skim coat, I would recommend applying a full-surface concrete contact primer designed for gypsum-based fillers and plasters. Otherwise, you might have adhesion problems on the very smooth surface.

we have a precast concrete basement standing. I have now informed myself at the hardware store about what I need for sealing the joints and for the basement living areas in terms of materials.

"precast concrete basement" probably means that you have so-called semi-precast walls with a cast-in-place concrete core standing.

But what is this about? - I suspect: the corners where interior walls meet the exterior walls. I would expect these interior walls to be load-bearing (also) precast concrete elements, but non-load-bearing also sand-lime brick or the like? - different materials would require consideration regarding the elasticity of the jointing. If one can already get answers from an expert like my predecessor here, it would be worthwhile in my opinion for a questioner to explain such details right in the opening post.