KLB production

How and according to which standards do we produce.

Environmental compatibility

For 35 years KLB has been setting standards and has been creating more out of pumice and expanded clay than just blocks. KLB - it’s a complete shell construction system from basement to roof, with the best building physics properties.


High-quality raw material, obtained through environmentally conscious mining, with simultaneous, near-natural recultivation, guarantees a long-term, emission-free use for a comfortable life in living areas with the lowest primary energy requirement through product-specific optimised and emission-free manufacturing processes. All demands, however modern or unusually architectural, can be realised with the multifaceted KLB range.


And after the useful life of a building? KLB thought of this as well, because KLB products can be disposed of without problems and are fully recyclable.

Natural raw material, environmentally friendly mining, near-natural recultivation

The pumice addition is a gravel-like loose rock, which is mined in an open pit. The outcropping worth mining is under an approx. 30 to 100 cm thick layer of topsoil with thickness ranges between 1 and 6 m. The mining is done using excavators, caterpillars or wheel loaders.

After mining the pumice gravel the pit is immediately levelled by reusing and spreading the saved topsoil. When mining pumice the terrain is thereby only lowered by the corresponding mining depth. No craters remain and no mountains disappear as is sometimes the case when mining other minerals.


Mining pumice is regulated by the State Pumice Law. According to it mining only occurs when it is connection mining or at least an area of 1 hectare is available for mining and it is ensured that the mined area is restored close to nature according to its prior use.
After pumice mining, farmers and forest owners are happy because the previously heavy ground is loosened, rain water is held better and no longer drains too fast through the pumice layer. The soil becomes more productive and former forest areas can be quickly reforested according to today’s state of knowledge.

Standard binders, clean water

Only standard cements according to DIN 1164, which are also appropriately prepared natural aggregates, are used as binders. For manufacturing KLB products only a very small portion of binder is needed, which depending on the strength of the corresponding block is 8 to 12 % of the aggregate portion.


Well water or tap water is used as water for preparation. The portion, here only a few litres, depends on the moisture content of the raw material. This is earth-moist due to storage, but it can also have become wet due to weather influences.

Environmentally friendly production, low primary energy consumption

The manufacture of KLB products is very environmentally friendly. Except for the above mentioned aggregates, the binder and water, no additional additives or added materials are used - no chemistry, no poisons - so purely natural.


The aggregate is fed to the mixing facility. There the light-weight concrete mixture is produced with a precisely-weighed binder quantity and a precisely dosed water supply.


The mixture gets into the fill box of the automatically operating block forming machine, which in turn fills the fill cart. The fill cart then drives over the steel forms, which are standing on a base board, several times and fills them. The block forms contain the required cores for slots and chambers depending on the later shape. Via load and vibration by imbalance drives the mixed product is thickened such that the blocks can be directly (pushed out of the form) demoulded. The finished and immediately demoulded blocks remain on the level base boards or sheets. The fresh blocks have such good strength (green strength) that they survive the continued transport movements until the initial hardening without damage.


They leave the area of the production machine and are deposited in an automatic elevator, after an alignment scrubber has removed loose parts and burrs.

The elevator can accept 20 or more base boards with blocks. From there a multiple fork lift takes the boards and drives them for hardening into a dry high-bay warehouse. The blocks set here and after 24 to 36 hours reach such strength that is sufficient to mechanically grip, pile, palette and bundle the blocks with steel bands.


In order for the mason to not have to rotate the blocks at the construction site, all KLB products are rotated and packetised such that the blocks arrive ready for processing manually or by machine, with the hollow chamber downward, at the construction site. Subsequently the blocks are packaged with a shrink cover to protect them from the effects of weather. Then they arrive at the storage location and have to sit there for at least 28 days until the final strength required by the standard is reached.


The KLB shrink covers as well as the KLB sacks of mortar are collected on the construction site and later picked up by the responsible waste disposal company. INTERSEROH takes over the disposal for large and small collection points for KLB, and sends them to recycling. The INTERSEROH manufacturer numbers of KLB is 25499 and 27852. The KLB multi-use palettes are taken back. As there is a total lack of chemical additives and the blocks are also not treated with thermal technology (autoclave or combustion process), the manufacture takes place without any contaminating exhaust gases or outgassing.


Due to the hardening omitting any kind of thermal treatment KLB blocks only require minimal primary energy consumption. Investigations by neutral institutes have shown that for manufacturing KLB blocks only about 190 kWh/t are required. Almost 90 % of this primary energy requirement occurs otherwise in manufacturing the cement used for the pumice construction materials. In the actual manufacturing including raw material mining, raw material transport and a freight share for the finished products only approx. 25 kWh/t are needed.