The Baden-Württemberg 2023 Environmental Technology Award in the “Material Efficiency” category goes to the Würth Group’s REINFORCE AC product. The system – a joint development by Würth and TOGE Dübel – allows aerated concrete roofs to be subsequently reinforced so that they have up to 80% more load-bearing capacity.
“Load-bearing roof surfaces are a basic prerequisite for equipping buildings with photovoltaic systems – and therefore important for the energy transition. REINFORCE AC from Würth ensures that roofs can be upgraded with little effort,” says State Secretary Dr. Andre Baumann.
From the left: Hans-Peter Trehkopf (Head of Construction Site Project Management at Adolf Würth GmbH & Co. KG), Sibylle Hepting-Hug (Head of the Climate, Sustainability, Resource Efficiency, Circular Economy Department at the Baden-Württemberg Ministry for the Environment, Climate Protection and the Energy Sector), Andreas Gerhard (Managing Director of Würth subsidiary TOGE Dübel GmbH & Co. KG), David Röck (Engineer at Adolf Würth GmbH & Co. KG) and Nikolai Sklarov (Engineer at TOGE Dübel GmbH & Co. KG). © unger+ Kreative Strategen / Jan Potente
Aerated concrete roofs make it difficult to install photovoltaics
The installation of photovoltaic systems on existing roofs promotes the energy transition and avoids new land consumption. But the systems are heavy. Industrial buildings in particular, which are 25 years old or older, often have roofs made of aerated concrete, the load-bearing capacity of which is not designed for the installation of a PV system. Until now, these roofs had to be dismantled if necessary and reconstructed from a more stable building material, such as concrete or steel. This procedure resulted in several tonnes of construction waste and newly produced concrete.
Subsequent reinforcement against waste of resources
With REINFORCE AC, the Würth Group has developed a system with which the load can be distributed across the roof surface. This is possible using screws and a reinforcing mortar that is pressed into the air capillaries of the aerated concrete. While the screws already support the existing reinforcement of the aerated concrete, they are used to anchor GRP or aluminium rods to the underside of the roof. They serve as additional external reinforcement and bending tensile reinforcement. This allows up to 80 per cent additional load-bearing capacity to be placed on the roof. REINFORCE AC was developed together with Toge Dübel GmbH & Co. KG, a subsidiary of the Würth Group, at the Reinhold Würth Innovation Centre CURIO.
From the ZiE to the general building authority approval
The solution is already available on the market; projects receive approval in individual cases (ZiE). General building authority approval from the German Institute for Building Technology (DIBT) is expected by summer 2024. “The special thing about our reinforcement solution is that it can be easily realised retrospectively and during operation. This saves companies considerable costs because they don’t need a new roof. The system also conserves resources because the individual product components can be completely recycled,” says Thomas Klenk, Managing Director of Adolf Würth GmbH & Co. KG for Purchasing, Product, Marketing and Research & Development.
