For renovating an open-pored plaster layer, a paint is made available that includes water, an inorganic binder on an alkali polysilicate base, a pigment composed of particles and a stabilizer. The stabilizer is composed of small particles on a silicate base, having an average diameter below 3 μm, wherein these particles are colloidal distributed in water because of their charge distribution. As a result, the stabilizer prevents an insoluble sedimenting of the pigment particles. Following the application of this paint, the desired and in particular the original color shade is again uniformly present across the complete surface, and the cohesive pores extending through the plaster layer are essentially still open. The sound-absorbing effect of the porous plaster layer is therefore not substantially impaired as a result of the renovation.