Can you paint the joint? Silicone no; acrylic yes

Silicone: there is no workaround

Low surface tension. Water sits in beads; so does paint. Fish-eyes, islands, a film that lifts after a month. No household primer turns a silicone bead into a paint substrate.

Smearing acrylic over silicone “so it will key” does not work either. Within a month the whole sandwich lets go.

If silicone sits where paint must go, replace it with acrylic. Full stop.

Acrylic: yes, after it has cured

Skirting, ceiling, interior frame: a low-shrink acrylic such as OTTOSEAL A205, and paint when the bead is stable. Count 24 hours as a minimum; fat joints or cold, 48.

“Paint immediately” sounds good on the tube. On site it often gives more adhesion trouble. I would rather wait until the acrylic is firm.

Hybrids and the “paintable” trap

Some MS polymers can take paint. The label does not promise the result stays pretty. Paint is stiff; the bead is elastic. As the house moves, it crazes.

“Non-crack” does not save shrink if you skip the wait.

How I tool if someone will paint afterwards

The painter’s first enemy is soapy tooling. Residue walks into the flanks and the paint lets go right there. A dry spatula, or a finisher meant not to spoil enamel. A little water, not a bucket of washing-up liquid.

Substrate degreased and dust-free, for the sealant and for the paint.

In the shower you do not paint the joint

Acrylic in the wet zone is not a lasting seal: it soaks and goes. If you want colour in the shower, you pick OTTOSEAL S100 (or another sanitary silicone) in the tile colour. There are plenty. The brush is not a plan B.