Dr Carl Riffer Baustoffwerke GmbH & Co KG
Since its foundation in 1918, Dr. Carl Riffer Baustoffwerke has stood for expertise in pumice products and the refinement of raw materials. At the production site in Neuwied/Rhine and at the headquarters in Mülheim-Kärlich, natural silicates are mined, processed and exported worldwide as high-quality lightweight aggregates and granulates. Masonry blocks made of natural pumice have been produced in Mülheim-Kärlich since 1850 and have been marketed under the Bisotherm brand name since the 1970s.
Since 2010, natural pumice has been sustainably processed and refined at the Neuwied site using state-of-the-art equipment and energy-efficient drying systems. Innovative processes such as precise crushing and sieving produce a sustainable lightweight aggregate with an excellent energy balance. This quality makes it a sought-after aggregate in numerous industrial sectors.
Dr Carl Riffer GmbH & Co KG has been the sole shareholder of ROTEC® Rohstoff-Technik and Bisotherm® GmbH since 1 January 2019.
ROTEC GmbH & Co KG
For over three decades, we have been dedicated to the extraction, processing and production of raw materials, substrates and lightweight aggregates at our Urmitz site. The extraction of natural pumice from the Eifel region by the former Klöckner GmbH from Duisburg began here back in the 1960s, primarily for use as an aggregate in regional building material production. With the takeover by ROTEC in the 1990s, the focus was placed on the refinement of this ecological raw material, resulting in the development of innovative lightweight aggregates with a wide range of applications.
At our site in Urmitz, Rhineland-Palatinate, we process ROTEC®naturalpumice using state-of-the-art technology. The raw material is carefully cleaned, crushed and screened so that it can be used as an environmentally friendly lightweight aggregate for applications such as substrates, soils and the production of lightweight concrete masonry. Our experienced sales team in Mülheim-Kärlich is ready to support customers worldwide in the optimal utilisation of our products.
Bisotherm GmbH
Bisotherm GmbH is a leading manufacturer of environmentally friendly and energy-efficient building materials that fulfil the highest demands of modern construction methods. Since its foundation in 1985, the company has combined ecological responsibility with technological progress and offers environmentally friendly solutions for future-orientated construction.
The extensive range of lightweight concrete blocks is suitable for a wide variety of building projects - from detached houses to large-scale projects. These building materials are characterised by their excellent thermal insulation properties, energy efficiency, sound insulation, stability, fire resistance and durability. This makes them the ideal choice for building owners who value sustainable and high-quality solutions.