Aufputz

Aufputz is a term used in German-speaking construction to denote the finishing plaster layer applied directly to a prepared substrate, such as masonry, concrete, or drywall. It forms the visible surface of a wall and is typically installed after an Unterputz layer. The Aufputz can be left plain, or opened to receive paint, wallpaper, or decorative finishes. It contrasts with Unterputz, which serves as the bonding coat and substrate for subsequent layers.

Common materials for Aufputz include cement-based plaster (Zementputz), lime-putz (Kalkputz), and gypsum-based plaster (Gipsputz). Interior applications favor lime or gypsum due to workability and humidity considerations, while exterior applications use cement- or lime-cement mixes for durability and weather resistance. The top layer is often reinforced with a fiber mesh or fabric, and priming may be required before painting.

Application involves surface preparation, bonding agent application, the base coats to even surface, and the final smoothing or texturing. Typical thicknesses range from 5 to 20 millimeters for interiors and greater on façades where irregularities must be leveled. After curing, the surface is prepared for finishing coats, such as paint or decorative plaster.

Aufputz provides a uniform, durable, and weather-protective surface, improves thermal and acoustic performance, and allows uniform textures. Disadvantages include potential cracking under movement, moisture-related issues if the layer is not breathable or properly protected against water ingress, and the need for skilled labor to achieve a high-quality finish. Regular maintenance may include repainting or re-plastering in damaged areas.

In electrical engineering and building services, the term Aufputz also describes surface-mounted installations, where sockets, switches, and conduits are mounted on the wall surface rather than concealed behind a wall.