Building Walls with Aerated Concrete Mortar: Application Guide

Aerated concrete masonry mortar is a special mortar that lets AAC, bims and brick blocks be laid into a straight, durable and planar wall. The right mortar and technique are decisive for the wall's load-bearing and thermal performance. This guide summarises the essentials.

Why a special masonry mortar?

Because AAC blocks are made to precise dimensions, they are laid with a thin-bed (thin-joint) technique. Instead of thick traditional mortar, an aerated concrete adhesive that forms a thin, uniform layer is used. This reduces thermal bridges and makes the wall flatter and stronger.

Thin-bed laying technique

In thin-bed laying the mortar is applied thin and even with a special notched trowel. Getting the first course level and planar determines the quality of the whole wall. Blocks must seat fully and joints must be filled.

Application steps

• Clean block surfaces of dust and loose particles.
• Mix the mortar lump-free to the manufacturer ratio.
• Level the first course; lay the following courses staggered.
• Spread the mortar in a thin layer with a notched trowel and seat the blocks evenly.

Common mistakes

Using overly thick mortar, dusty un-wetted surfaces, an unlevel first course and empty joints are the most common mistakes. They cause wall unevenness and loss of strength.

To choose a suitable mortar for your project, review Datex GZ121 aerated concrete, bims and brick mortar and get support from the Datex team.