Lamella Roofs
Porträt des Konstrukteurs und Städtebauers Friedrich Zollinger, 1937/38, Foto: Privatbesitz
Zollinger Lamella roof being built in Merseberg (Open Source) 1922 On November 25th 1924 Hugo Junkers applied for his first patent (No. 459038) for his iron lamella halls. They proved enormously succesful in Germany in between wars.
Image: Buckhard Franke
Patent file drawings for patent nº 462881, an improvement over Junkers’ first patent.
Lamella Roofs are a particular case of a 4-way reciprocal frame structure in which 2 linear elements rest on the middle point of a third, all members being the same. They were devised by Friedrich Zollinger from 1910 onwards. Zollinger was then Building Comissioner and City Architect of Dessau, Germany, and faced with the challenge of providing housing solutions for an increasing population within a tight city budget. Publicly funded new buildings was prohibitive, thus Zollinger took the approach of focusing in the extension of existing buildings. In most cases foundations were inadequate to support the constuction of an additional level in masonry, and to complete the challenge, the roof construction of typical houses consisted of high pitched trusses with structural elements on the section that blocked any possibility of generating a livable attic space. Zollinger’s solution was a structural system to substitute this roof construction allowing for a clear loft space using the same building outline and with inexpensive, readily available materials, mainly wood planks and simple hardware. Its ingeniousness lies at its ability to respond to constraints with a conceptual hybrid between a laminar and reticular structural model. Its main weakness was the lack of rigidity of the joint, solved by the sheathing planks acting as a diaphragm, but this was the issue most improvements that have picked up on the system have focused their attention, since it is wherethe main room for refinement and thus for material efficiency improvement remains.
Archiv Bernd Junkers - Junkers’ prefabricated, lightweight lamellae could be shipped, flown or even taken on the back of donkeys if necessary, anywhere in the world, to allow easy for deployment of hangars in the explosive expansion of the aviation era in the 1930s that Junkers, aeronautic engineer, pioneered himself.