Crepissage is a traditional French technique used in the art of plastering walls. It involves applying a rough layer of plaster to a surface, which serves as a base for subsequent layers. This method helps improve adhesion and creates a textured finish that can enhance the aesthetic appeal of buildings. The process typically includes mixing sand, lime, and water to create a workable plaster. Once applied, the crepissage layer is allowed to dry before additional layers are added. This technique is often used in both residential and commercial construction to achieve a durable and visually interesting wall surface.