"Himmelsstürmer" Lookout Tower in Schwäbisch Gmünd, Germany

A staircase with 209 steps in the area between the internal and external walls leads to the tower top.

The structural analysis of the "sky climber" was created by Andreas Wirth from Freiburg, who used RFEM and the RF‑LAMINATE add‑on module.

Structure

The tower has a square base area with lateral lengths of 17.7 ft. The inner tower consists of cross‑laminated timber slabs with three layers of a thickness of 4.7 inches. The outer tower was built with CLT elements as well. These consist of seven layers and have a total thickness of 7.8 inches.

There are 123 openings arranged in the external walls. Thus, visitors can always enjoy the outdoor scenery. The structural components were precast to a great extent. The inner tower consists of two tubes. The outer tower was divided into three construction sections. Each section was subdivided into four L‑shaped corner elements.

The structural connection in the vertical joints is ensured by numerous fully threaded screws. They were crosswise screwed in through the vertical joints with an angle of 60° relative to the transversal direction of the slabs. In the horizontal joints, the CLT elements are connected to each other by slotted sheets and dowels.

Once the Garden Show ends, the lookout tower will continue to be operated by an association. Thus, visitors will still have the possibility to enjoy the incomparable view over the landscape park of Wetzgau.