Interior plaster with voids - How to repair plaster defects


The basic plaster on your walls serves as a basis for decorative plasters, wallpapers and paintings. If these are getting old, they have to be renovated. In this case, smaller or larger repairs are often required, including the rehabilitation of voids.

Why are cavities formed on the interior plaster?

The plastering of the walls is usually done only once. Later it will only be renovated or renovated. Hollow spots or cleaning bubbles are usually the result of insufficiently moistened areas during plastering. As long as there are smaller areas, you can neglect them. If the ground becomes unstable, action must be taken.

Before you start renovating, the walls must be smooth. For this, old dowel holes are filled or cracks are filled out. Hollow areas in the interior plaster, on the other hand, have to be renovated more elaborately. But what happens if the walls sound hollow or the interior plaster crumbles?

How to clean up the voids?

Start with a diagnosis first. Missed defects can later lead to a coating not holding properly afterwards. In the worst case, this means - rework! This is how you should proceed:

  • Examine the plaster surface for voids, make a knock test
  • Remove the hollow-sounding spots, as well as loose and loose plaster.
  • Wet the plaster surface with water to assess the absorbency of the substrate.
  • If the suction behavior varies, the surface must be solidified with a deep plaster interior before further treatment.

How are the damaged areas repaired?

Before you use a restoration plaster to clean up the damaged areas, they must be completely clean. Smaller holes or bumps should be filled with a putty, for larger holes a plaster in two layers is recommended.

To do this, throw the first layer with a little trowel onto the previously wet wall, smoothing is not necessary. After a reasonable drying time apply the second coat with a trowel. This is removed with a cleaning bar. If this layer is also tightened, the surface can be rubbed flush with the float.

Tips & Tricks

It is essential to observe the information on the drying times of the restoration plaster before applying the next layer of plaster or a wallpaper. If this is too short, you have to start over in the extreme case.

Artikelbild: vitalikaladdin / Shutterstock


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