The sustainable and innovative wooden modular construction with its extremely short construction time aided the decision to build 32 wooden schools by 2025 in Berlin. First 6 schools have been successfully built and new schools are under construction by The Senate Department for Urban Development & Housing. Metsä Wood’s Kerto® LVL beams are used for offsite production.
Kaufmann Bausysteme in Germany is building ovet 30 wooden schools made of wooden modules. They use Metsä Wood's Glued Kerto LVL (GLVL) as 8-m long beams. Image Credit: Metsä Wood
Modular Wood Construction – Fast and Economical Construction Method
Wooden modular construction has experienced an extreme boom in recent years. The main reasons for this are increased sustainability requirements and cost-effectiveness of prefabricated wood-based modules. The City of Berlin wants to establish itself as one of the world's major metropolises for wood construction. Currently, three-storey wooden schools are being built in Berlin by Austrian prefabrication constructor Kaufmann Bausysteme (KBS). "6 schools have already been built and a total of 32 schools are to be built by 2025. The speed of the offsite construction method was a decisive factor. With the prefabricated wooden modules, the construction time can be halved," explains Sebastian Hagspiel from Kaufmann Bausysteme.
A Lightweight High-performance GLVL Wood Beam is an Alternative to Steel
One school consists of nearly 100 modules, each 3-m wide and 8-m long. All modules were prefabricated offsite and assembled on the construction site. To achieve a column-free floor plan for classrooms, 8-m long beams had to be used at the joint of the modules.
"For structural reasons, glulam was not suitable for this project. Steel beams were also not a solution for us or the architects," describes Sebastian Hagspiel, Project Manager at Kaufmann Bausysteme. The structural designers finally decided to use beams made of the high-performance and easy-to-process GLVL (Glued laminated veneer lumber).
Kerto GLVL for Long-span Beams
The GLVL was manufactured by Holzwerke Bullinger using Metsä Wood’s Kerto LVL. Ingo Faller from Bullinger’s sales department describes the process as efficient: "We have updated our standard glulam process so that we can use LVL beams. The GLVL beams have a high bending strength. In the GLVL process, laminated veneer lumber (LVL) beams are glued together. Compared to glulam, LVL is uniform in quality and therefore has an extremely high static load-bearing capacity. As a result, GLVL beams have a much higher flexural strength. Interestingly, LVL is stronger in strength-to-weight ratio than steel.”