Painting concrete walls and lime plaster in the basement yourself - Preparations?

Hello,

I am planning to paint 3 basement rooms in our new building over the weekend as a DIY project.

The walls are made of concrete (WU concrete) and lime plaster. Ceilings are reinforced concrete, already plastered.

I plan to proceed as follows:

- Sand the concrete walls
- Brush the walls with a broom to remove dust
- Lay out room fleece on the floor
- Tape off light switches, exposed electrical cables, windows, etc., or cover them with foil and tape at the edges
- Then start painting the ceilings, first the corners with a brush, then the surface, always in squares and crossing each square
- Then paint the walls, away from the light
- Overpaint lime plaster walls without sanding
- Probably do a second coat.

Am I doing this correctly or is this going to be a total botch?

Primer. Primer first. Otherwise it will peel off again. Karsten

Primer. First primer. Otherwise it will peel off again. Karsten

Thanks for the hint. I just looked at the substrate preparations. It says here

"Plasters of mortar group PII and PIII/compressive strength according to DIN EN 998-1 with at least 1.5 N/mm2: Coat firm, normally absorbent plasters without pretreatment. On coarse porous, sandy, absorbent plasters, a primer with OptiGrund or CapaSol."
or
"Concrete: Possibly remove existing release agent residues as well as chalking, sandy substances."

As mentioned, the non-concrete walls are troweled lime cement plaster. Is a primer still necessary?

I would do it so that it sucks less. If not necessary, it doesn't hurt. Tiegfrund is also cheap. Karsten

Ok, regarding the instructions from Caparol, the corresponding primer says "For commercial use only. May cause severe injury or death if inhaled. Etc." Doesn't sound too good. Can I use a different primer, for example from the hardware store?

I also once read something about diluting the first coat with 10-20% water, which is supposed to replace the priming (?).

Additionally, I discovered a small wall made of solid gypsum boards. I certainly have to prime here, or is there another option?

Honestly, you can use any primer, even the one from Bauhaus or OBI. 10L for 20,- is more than enough. I’m not familiar with the diluted first coat, but it doesn’t save any work anyway. Karsten