Cobiax

About

Cobiax: Redefining Building Possibilities – Wider Scopes Modern Slab Technology for a Sustainable Future

Cobiax is a leading provider of innovative void forming systems for reinforced concrete slabs. For over 20 years, the company has been at the forefront of voided slab technology, offering sustainable and cost-effective solutions for the construction industry.

Headquartered in Bielefeld, Germany, Cobiax has implemented its patented technologies in projects worldwide, saving over 2 million tons of concrete and 180,000 tons of CO2 emissions to date. The company’s award-winning portfolio includes the versatile Cobiax SL system and the easy-to-install Cobiax CLS system.

At the core of the Cobiax system are plastic void formers that replace solid concrete in slab interiors. This significantly reduces slab weight, material usage and carbon emissions. Over 14 million square meters have been constructed with up to 35% less concrete, saving 2 million tons of concrete and 180,000 tons of CO2.

There are two main Cobiax products:

Cobiax SL – For increased spans and thinner slabs. Features integrated bonding reinforcement in .6 and .6E variants. Modules or individual components available.

Cobiax CLS – For all slab types. Very easy installation by laying half-shells adjacent to each other. Seven shell sizes create 19 void patterns. Approved worldwide.

Both systems enable the same load capacities as solid slabs with reduced slab thicknesses and weights. This decreases materials, transport and foundation requirements. Cobiax slabs are proven to meet stringent structural standards.
Additional benefits include:

Less excavation, columns and construction time
Lower project costs
Increased available space
100% recycled plastic material

Cobiax voided slab technology: the sum of all the advantages

Our advantage is multi-dimensional. The voided slab building method is not only more sustainable than any solid construction. Rather, when all the cost aspects are taken into account, it is also cost effective, and – thanks to the excellent Cobiax quality assurance systems – it is extremely safe.

Safe

Our voided flat plate slab constructions fulfill the most stringent international standards.

Due to the reduction in the weight of the slabs, the risks of sudden loads are reduced (e.g. during an earthquake). Our quality assurance guidelines set standards for plastic-based building materials; they ensure permanent stability for many generations to come.

Sustainable

The use of plastic and voiding material replaces at least 25 – 30% of the concrete used for conventional building methods. This reduces the CO2 emissions, even during the production; the amount of building sand required is also reduced. The void formers themselves are made of 100% recycled plastic; the construction remains stable over several decades and centuries.

Profitable

The economic advantages: The required volumes of concrete that need to be transported, drops by about 30%, as does the transport load. The bearing components of the construction can be made lighter and more elegant, due to the reduction of the load to be carried; this reduces the costs even further. Thanks to the lighter design of the building itself, the available net space also increases; this in turn, leads to an increase in the possible returns.

Both technologies feature interlocking plastic void forms that replace solid concrete in slabs, reducing weight and materials while maintaining structural performance. This enables wider spans, thinner slabs, and lighter foundations compared to traditional designs. Depending on the system, concrete savings range from 25-35%, lowering costs, environmental impact, and construction time.
Our void forms are made from 100% recycled plastic and engineered for longevity, with quality assurance guidelines ensuring stability for generations. The reduced slab weight also enhances seismic resilience. Overall, the Cobiax system delivers on safety, sustainability, and profitability.

With simple integration into standard designs, we empower structural creativity and flexibility. The company partners with engineers worldwide to optimize projects across sectors, from commercial buildings and stadiums to residential construction.
Notable projects featuring our slabs include the Microsoft Headquarters in Munich, the Quartier Heidestrasse complex in Berlin, the National Stadium in Warsaw, and the Assima Tower in Kuwait City. In the Berlin project alone, our void forms saved 13,000 tons of concrete and 1,100 tons of carbon emissions.

From planning to installation, we provide comprehensive support, including design software, technical documents, training, and consultations. The company continues to drive innovation in voided slab construction through rigorous R&D centered on creating value for customers and the environment. With proven solutions ready for widespread adoption, Cobiax is leading the industry toward a more sustainable future, one project at a time.