Unfortunately we do not have a product to recommend for over painting masonry paint applied to patio slabs.

This would need to be removed prior to an appropriate floor paint being applied.

Assuming this is done, a damp proof membrane is present, they are clean, dry, sound and prepared as detailed in the technical data sheet we can recommend Coo-Var Acrylic Floor Paint.

This can be mixed to many RAL, NCS or BS colours in a semi gloss finish.