Pelgulinna State Secondary School

Pelgulinna State Upper Secondary School (PERG) is a landmark of sustainable architecture, standing as one of the largest mass timber educational buildings in the region. The project’s structural honesty is defined by its exposed hybrid skeleton, where a rhythmic, double-stepped external glulam grid serves as both the building’s primary character and a robust load-bearing framework.

The interior logic relies on a sophisticated synergy between glulam post-and-beam systems and cross-laminated timber (CLT) wall and floor panels. This monolithic timber concept was realised with extreme technical efficiency; the use of prefabricated elements allowed for an exceptionally fast assembly phase, with large CLT slabs and massive glulam sections forming the school’s airy, multi-storey atriums and expansive common areas.

The engineering feat of the building lies in its ability to handle significant architectural cantilevers and large open-plan spans. To support the dramatic overhangs above the entrance and communal zones, the timber frame is strategically reinforced with a massive steel truss integrated directly into the second-floor wall structure. This hybrid approach provides the necessary stiffness to allow the heavy timber volumes to "float" without compromising the architectural vision.

Precision was the cornerstone of the construction process, managed through a rigorous BIM-integrated workflow. Every bespoke node and high-strength hidden connector was engineered to meet strict fire safety requirements while maintaining the slender, optimal aesthetic of the timber. The result is a high-performance educational environment that showcases the innovative potential of combining modern steel engineering with the warmth and sustainability of mass timber.