Glue aerated concrete - how does it work?

Autoclaved concrete blocks are almost always executed as plan stones. This makes time-saving and easy bonding of cellular concrete possible instead of elaborate walls. What this means, and how to do it right, is explained in detail in this article.

Glue instead of walls

In conventional walls, stones must be placed on a mortar bed, and walled in addition to the butt joint, to ensure an exact match to the adjacent stones and to compensate for bumps in the head area using a vertical joint.

However, ladders are made to exacting dimensions - they fit seamlessly together. This will not create a vertical gap between the stones. This also significantly improves the thermal insulation of the wall.

Glue aerated concrete - how does it work?: aerated

The longitudinal joint between the stones can be made very narrow because of the exact matching stones. Common are joint widths between 1 and 3 mm. Thin-bed mortar is used for this. Therefore one speaks also of the "gluing" of aerated concrete blocks.

Uniform mortar application

Because of the small joint width and the exact fit of the stones and the joint must be designed to match. The mortar application must have exactly the same thickness at all points. Various tools can be used to apply the mortar:

  • notched trowel
  • special spatula for the Porotonbau (recommended)
  • mortar carriage

Spatula and mortar sled should correspond exactly to the stone width. This ensures a really even high mortar application at all points. Here must be worked very precisely, otherwise the wall can not be straight.

mortar consistency

Only the specially designated thin-bed mortar (= "glue") may be used. He must have the exact right consistency in processing, otherwise the strength and stability of the masonry is not guaranteed.

Only the amount of mortar that can be processed in a short time may be mixed. When stirring, use a stirrer. It is only allowed to stir in a very slow speed. There must be no air bubbles in the mortar when stirring. This endangers the adhesion of the mortar.

test strips

The strip test can be used to check whether the consistency of the mortar is sufficient: Apply a small amount of mortar with a toothed spatula.

If the resulting strips run to each other, the mortar is too soft. If uneven streaks occur, the mortar is already too strong and can no longer be used.

Tips & Tricks

If you lift an already bricked stone, its underside must be covered everywhere evenly with the thin-bed mortar. Always place stones exactly vertically from above.