Yosima clay plaster can easily be applied to gypsum board. The gypsum board must first be primed with a deep primer to level the absorbency of the gypsum board and possible filler areas. Afterwards, the gypsum board must be primed with a plaster primer containing quartz. Please note that YOSIMA clay plaster is not crack-bridging. Cracks that occur at the filled joints of the plasterboard will also be visible in the clay plaster applied on top. It is therefore recommended to reinforce the joints of the gypsum plasterboards with a fabric strip or a fleece before filling.