Fill the concrete wall properly

When a concrete wall is to be filled, it usually means repairs to slits, cracks and holes. The transition from puttying to plastering is fluid and is defined in principle more on the surface area to be machined than on the difference between putty and plaster.

Difference between filling and plastering

Mortar is applied both when filling and when plastering a concrete wall. The usually finer putty mortar is used to fill in all construction-related unevenness and interruptions of the plaster layer and the substrate. This includes damage such as plaster exfoliation, butt joints in the wall or cable and pipe ducts.

In a second function and meaning, the filling is called a technique and applied to apply a full-surface plaster. The execution of spatula technique resembles the design of a rough structure plaster, which receives a individual surface structure by coating techniques.

Create an optimal connection

The aim when filling a concrete wall is the optimum connection of the filler with the substrate and, if necessary, the plaster. Therefore fillers or mortars consist of ingredients that are also present in plasters and concrete walls. Lime mortar is often used and the connection with wall or plaster is reinforced by a primer.

Ideally, a homogeneous compound is created, which guarantees maximum durability and the overall properties of the concrete wall and the plaster, as does not affect the diffusion. For wet concrete walls and plasters, this effect can be enhanced by wet-on-wet processing.

How to fill a concrete wall

  • lime mortar
  • Possibly color pigments
  • water
  • primer
  • trowel
  • joint iron
  • trowel
  • brush
  • spatula
  • Mortar cup made of rubber

1. Prepare

Remove any loose ingredients from the area to be filled. These include crumbling plaster and concrete, sand, pebbles and dust.

2. Mix the mortar

Stir the mortar according to the manufacturer's instructions and add the desired color pigments if necessary.

3. Apply primer

Spread the primer with a brush on all surfaces where the mortar later hits the concrete wall and / or plaster.

4. Fill mortar

"Lubricate" the mortar in portions in the prepared spatula points. Squeeze gently and allow the mortar to stand one to two millimeters above the surface.

Tips & Tricks

With special additives, you can enhance special properties such as moisture resistance and adhesion in your mortar.

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