Lightweight modules can be quickly and easily glued to roofs with insufficient structural strength
Lightweight solar modules face a structural challenge
The problem of lightweight industrial buildings, which do not meet the structural requirements for a solar power system, was long considered insurmountable. For W. Marwitz Textilpflege GmbH, however, it has now been achieved despite a structurally weak roof: On the roof of its facility in Lüneburg, the family-owned company will now generate its own solar power—despite challenging structural conditions. This was made possible by special lightweight PV modules that do not require a heavy substructure and are bonded directly to the roof surface.
May 2026. For a long time, the laundry had been considering the idea of generating its own electricity using a photovoltaic system. However, due to the building’s lightweight construction, a standard solar system could not be installed at first, as a structural analysis confirmed that conventional PV systems were too heavy for the roof.
“But it was clear to us that we didn’t want to give up, despite our structural issue. For us, sustainability also means looking for solutions when standard approaches don’t work,” explains Mirko Wilhelms, Head of Operations.
New possibilities despite limited structural capacity thanks to lightweight adhesive-mounted PV modules
An article in pv magazine drew the company’s attention to modern lightweight PV modules that are installed using adhesive. These specially designed solar modules do not require a traditional mounting structure and are therefore particularly suitable for roofs with low load-bearing capacity.
After extensive research and positive references, Marwitz decided in September 2025 to have SunOyster Systems GmbH implement this solar solution.
The contract was awarded in February 2026, and installation of the system began shortly thereafter. In the first phase of construction, approximately 99 kWp of capacity was installed. A total of 225 modules were used, which were adhered directly to the roof surface. “Despite minor challenges on the construction site, the installation proceeded very quickly. The modules were installed in just four hours,” reports Mirko Wilhelms.
With the new solar power system, the company will be able to meet part of its electricity needs on its own in the future while reducing its reliance on external energy sources. The adhesive-mounted lightweight modules come with a 30-year performance warranty.
