Plaster gas concrete blocks - you have to pay attention

The porous structure of aerated concrete blocks brings significant advantages in terms of material properties. But it also makes it difficult to plaster. Not all plasters are suitable for aerated concrete blocks, and even the plastering itself must be considered a lot. Instructions can be found here.

Suitable cleaning methods indoors

Gypsum plaster is best suited as a concealed installation on walls made of aerated concrete blocks.
Also lime cement plasters or gypsum lime plasters are suitable as the first layer of plaster, but in each case to ensure sufficient adhesion of the plaster mixture.

By contrast, there are no restrictions on the decking (second layer of plaster).

Plaster gas concrete blocks - you have to pay attention: concrete

Alternative to plastering indoors

It is also possible to grind the aerated concrete surface, spackle and provide it with a primer and ink layer. This is only possible with non-load-bearing walls. The color used must be mineral. Non-permeable colors are not suitable.

Thin-film plasters may also be suitable for non-load-bearing walls. The layer thickness is then only 3 to 5 mm. In individual cases, however, it must first be tried out whether the adhesion of the plaster is large enough.

exterior plaster

Today, mineral light plasters are used for exterior plaster. In some cases, they can only be processed in one layer. In exceptional cases, even layer thicknesses of less than 20 mm are possible. However, care must be taken that the plaster used is actually suitable for use on aerated concrete.

Plaster aerated concrete blocks indoors

  • Aerated concrete blocks
  • Plaster plaster as a concealed plaster
  • Finishing plaster (optional)
  • putty
  • adhesive paint
  • Cleaning trowel, trowel
  • mop bucket
  • Drilling machine and agitator or alternatives

1. Check masonry

The masonry must be absolutely dry, dirt and dust-free. Contaminants that reduce adhesion must not be present and must first be removed. Repair damaged stones. This can be the case, for example, with spalling or damaged corners. Be sure to fill in open joints.

Pay special attention to the areas where different materials meet. Here can be necessary to attach plaster bridges. Install plaster bridges at a distance of about half a meter.

2. Pre-wetting and adhesion

For better adhesion of the plaster, pre-wet the wall and apply an adhesive coat (recommended).

3. Apply flush-mounted

Apply the plaster with the trowel and remove it cleanly along the cleaning slats. Let dry.

4th surface plaster

Then then the top coat can be attached.

Tips & Tricks

An alternative to plastering is also the application of ceramic tiles directly to the masonry by means of a special pressure-sensitive adhesive.

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