Concrete Lightweight Ceiling
EIGNER Betonmanufaktur GmbH & Co. KG
Concrete Lightweight Ceiling uses 3D-printed concrete segments as an integrated formwork to revive an almost forgotten method of reinforced concrete ribbed slab construction. The use of hollow cores enables a 40% reduction in concrete and requires 30% less reinforcing steel. By combining these innovations with a CO₂-optimised recycled concrete mix, the system achieves a 35% reduction in CO₂ emissions compared with conventional solid slabs. Concrete is used only where it is needed.
Award winner 2025 in the category »Konzept«»The jury is impressed by the optimised ceiling construction. It demonstrates the potential that 3D printing of concrete can offer. The CO2 consumption of the Concrete Lightweight Ceiling was reduced by 35% compared to the original design – a redefinition of the almost forgotten reinforced concrete ribbed ceiling.«
Michael Volkmer
Three questions for Werner Greiner, sales manager
How did the idea for "Concrete Lightweight Ceiling" first come about?
Our goal has always been to demonstrate that even solid construction with reinforced concrete can be truly sustainable. While concrete is often seen as environmentally unfriendly, we wanted to demonstrate that innovative approaches can enable more resource-efficient use. This led us to develop a material-optimised construction method that brings together strength and efficiency, helping to make solid construction more sustainable.
Were there any breakthrough moments in the course of development? What were the biggest obstacles you faced?
The highlight was the moment the lower formwork was removed, and the shape and precision of the rib structure were revealed for the first time. We didn’t face many major challenges – the biggest was producing the tunnel-shaped moulds. This called for exceptional precision and stability to shape the complex forms accurately, achieving the best possible result.
What are the next steps for your project as you look to the future?
Our aim is to raise awareness among planners of ribbed and cassette ceiling systems, along with other material-optimised ceilings. These construction methods offer huge potential to save both materials and resources. By sharing our research, educational initiatives, and practical examples, we want to show that efficiency, cost-effectiveness and sustainability can all go hand in hand in modern solid construction.
