The office building in the town of Kristiansand is southern Norway's first and largest commercial building made of mass timber. It has proven to be economically competitive against standard steel and concrete buildings. Designed by Oslotre Architects and built in record time with a high degree of prefabrication and innovative solutions, the building achieved a 53 % reduction in greenhouse gas emissions and is taxonomy-aligned. The building is an all-timber building with wood as the constructive, insulating and protective material. The innovative green-painted and curved wooden façade has gained international attention, making LUMBER 4 one of the most published buildings on social media globally in 2023. Today LUMBER 4 serves as headquarters for Green Tech companies. 

"Winning this award for the world's best mid-rise office building with our all-timber LUMBER 4 signifies a transformative shift in the construction industry. We are advancing toward more sustainable, circular, and biologically-based architecture, a vision Oslotre has championed for nearly 15 years. It is immensely gratifying to see our efforts recognized," says a proud Jørgen Tycho, Creative Director at Oslotre Architecture & Construction Technology.

Photo credit: Kyrre Sundal

Photo credit: Kyrre Sundal

Photo credit: Kyrre Sundal

Photo credit: Kyrre Sundal

Photo credit: Kyrre Sundal

Photo credit: Kyrre Sundal

Photo credit: Kyrre Sundal

Photo credit: Kyrre Sundal

Photo credit: Kyrre Sundal

Photo credit: Kyrre Sundal

Photo credit: Kyrre Sundal

Photo credit: Kyrre Sundal

Photo credit: Kyrre Sundal

Photo credit: Kyrre Sundal

Photo credit: Kyrre Sundal

Technical sheet

• Building/Project Name: Lumber Building 4 
• Address: Lumberveien 27, 4621 Kristiansand 
• Municipality: Kristiansand 
• Completion Date: 2023 
• Client: Skeie Eiendom 
• Contractor: VEF Entrepreneurs 
• Project Management: Innovatre 
• Architect: Oslotre AS 
• Architectural Team Members:
• Jørgen Tycho Architect MNAL, Christoffer Imislund m.arch., Katrin Wilde Sampaio, Kristine Karklina 
• Interior Architect and Team Members :
• Amanda Skadeberg – Oslotre 
• Landscape Architect and Team Members :
• Hanne Alnæs and Kaja Tellefsen Wivestad from Asplan Viak 
• Consultants:
• Structural Engineer (Wood): Oslotre AS
• Structural Engineer (Concrete): Multiconsult AS
• Structural Engineer (Building Services): Sweco AS
• Acoustic Consultant: Sweco AS
• Ventilation Engineer: Rivco AS
• Electrical Engineer: Bravida AS
• Water and Sewage Engineer: Vianova
• Fire Safety Engineer: Rambøll
• Fire Safety Engineer (Wood): Rambøll
• Fire Safety Engineer (Concrete): Rambøll
• Ecologist: Rambøll
• BREEAM Consultant: Rambøll
• Delivery of Solid Timber and Glulam: Splitkon
• Gross Floor Area: 3106 m2 
• Photographer(s): Kyrre Sundal, Christoffer Imislund/Oslotre