A stone wall made of natural stone plaster

A stone wall made of natural rock can be upgraded and changed in some cases, both functionally and visually, by plastering. Unlike the plastering of concrete or bricks, the specific characteristics of the particular rock are decisive here. Many plasters need to develop adhesive properties.

Rock-dependent plastering technique

The plastering of a stone wall can cover unsightly surfaces or form a smooth course of the wall from the uneven wall surface. Most stone walls have joints that can be filled to a certain extent during plastering. The choice of Putzart and technology depends heavily on the rock.

Soft natural stones such as limestone and sandstone bring similar absorbency and adhesion to concrete. Hard rocks like basalt and granite have very small pores and a relatively smooth surface. For plastering, it is necessary to use low-viscosity types of plaster and aggregates which have a high binding and adhesive power.

Make surfaces and plaster liable

The crucial feature of a plaster is that it holds. Several factors influence the adhesive behavior:

  • Composition of the plaster
  • Adhesive effect
  • diffusion behavior
  • Number of plaster layers
  • External influences such as weather or humidity

The construction of the stone wall as drywall or mortared wall additionally influences the plastering. Generally, joints are the "weak spots" when plastering and should be neutralized as much as possible. Ideally, the open or filled with mortar joints are blinded. The plaster either the "bleeding" in cavities or contact with the mortar is impossible. As a result, the plastering can be adjusted exclusively to the properties of the surfaces of the stone wall.

Primer from a cement slurry

When plastering a wall, a primer must be applied in all cases and for every kind of stone. In most cases, a so-called cement slurry is used. It settles on the spin on and in the pores of the stone wall. Two to four additional layers of plaster are applied to this primer bonding layer.

Aid sacrificial plaster

Dryness of the stone wall is an important prerequisite. If efflorescence or other signs of moisture are detectable, repair with a sacrificial plaster is necessary. This strongly absorbent plaster is applied temporarily and "pulls" the moisture out of the rock.

Tips & Tricks

For veneering and sealing open or mortared joints, you can use slate tiles that harmonize with all natural rocks.

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