Brick (unfilled)

Masonry bricks are construction products made of fired clay. A distinction is made between vertically perforated bricks and shaped units for load-bearing and non-load-bearing masonry, and masonry panels (brick elements as prefabricated assembly units), each for external and internal walls of buildings. This EPD covers bricks for both protected and unprotected masonry; see also the bulk density range of 550-2000 kg/m³. For highly thermally insulating bricks, pore-forming agents are added during production. Masonry bricks can additionally be filled with various insulating materials. These bricks are covered in a separate EPD. The basis of the life cycle assessment results in this EPD is an average across all German plants, calculated as a weighted mean based on the share of the individual production sites in the total annual production. A brick with a bulk density of 575 kg/m³ was selected as the representative product.

After the clay has been extracted in the open pit, it is transported to temporary storage on the factory premises. The mechanical processing of the clays, such as crushing and mixing, takes place in the pan mill and the rolling mills. The above Basic materials are comminuted (processed), mixed and moistened in certain optimized proportions. This is followed by storage in the swamp house. The porosity agents are added before or after storage in the sump house. After passing through the fine rolling mill and adding more water, the blanks are shaped by extrusion with appropriate mouthpieces and a downstream cutter. The material formed in this way goes into the dryer, which is mainly operated with the waste heat from the tunnel kiln. The drying time varies depending on the format and bulk density and is usually 24 hours. The dried blanks are then fired in a tunnel kiln at approx. 1000 ° C for a maximum of 24 hours. The combustion of the porosity causes fine porosity. To produce flat bricks, the bricks are ground flat. The bricks are stacked, shrink-wrapped in recyclable PE film or strapped with polyester or steel straps. The energy requirement for brick production mainly relates to the firing process and drying. The electrical energy is mainly used in processing.

Depending on the wall construction, masonry bricks of various shapes are used for solid components such as basement walls, external walls, and load-bearing and non-load-bearing internal walls.