Clay and air
We at the Lehm-Laden can now look back on a long cooperation with the Ziegelai Gumbel brick factory. This small family business digs the clay regionally, namely on its own property, and uses it to produce air-dried, very high-quality earth bricks using the classic extrusion process. The brick factory is based in Central Germany, where the reddish clay soil gives the bricks a striking red color.
In the pan mill (please imagine two vertical millstones moving around a vertical axis in a flat bucket and crushing and mixing everything on the bottom of the container), the clay is crushed and, if necessary, mixed with additives. Extrusion creates the different stone formats. The clay is solidified into bricks without firing, only by air drying.
Production
The manufacturing method is as simple as it is traditional and efficient: production can be accomplished using minimal energy and involves only drying time.
The bricks are walled with a suitable masonry mortar. A light clay mortar is recommended for light clay bricks, and a heavy clay masonry mortar for heavy clay bricks. Due to their special suitability as a plaster substrate for a clay plaster, the light clay bricks in particular function as insulation, masonry and plaster base in one building material.