Business and Institutional

Merkur City Offices

AustriaContractors: Ruckenstuhl GmbH

Merkur City Offices - Gypsum International Trophy 2025

Project description

In the historic center of Graz, Merkur Versicherungen AG completely renovated an office building complex. The extensions and the roof renovations were carried out using lightweight construction and clad steel structures. Before the actual interior work could begin, approximately 1.600 meters of steel beams and columns had to be clad on all sides in fire resistance class EI 90. The work was carried out at great height and outdoors. The greatest challenge was adjusting the new roof landscape with the skewed intersections, vertically inclined walls, complicated roof surface intersections, and elaborate ceiling cladding with cantilevers for indirect lighting.

Main information

Building size

12 000 m²

Building purpose / type

Office building

Building owner name

Merkur Versicherungs AG

Architect name

Thomas Lorenz ZT GmbH

Contractors

Ruckenstuhl GmbH

Company name: Ruckenstuhl GmbH

Main Representative: Johann RUCKENSTUHL

Other Representative: Arnold PRISTERNIK

Number of collaborators: 70

Specialties: Soundproofing, Fire Protection and Acoustics Constructions, Ceiling Cladding, Door Elements, Dry Screed

Founded in: 1995

Biography: They specialize in planning and installation work across the entire spectrum of acoustic and drywall construction. Their focus lies on fire, sound, and thermal protection. Theiy install ceilings, wall claddings, and partition walls.

Website: www.ruckenstuhl-gmbh.at

Key Challenges

Executing rooftop extensions and attic expansions using lightweight or clad steel structures
Cladding approximately 1.600 meters of steel beams and columns in EI 90 fire-resistant materials before starting the interior work. These tasks had to be performed at great heights and in open-air conditions, requiring weather protection.
Achieving a seamless and refined appearance by meticulously spackling all surfaces to be free of visible light streaks, emphasizing aesthetic quality.

Key Achievements

Successful Renovation of Historic Buildings: The project involved the complete renovation of a historic Gründerzeit building complex in Graz’s city center, preserving its architectural heritage while upgrading its functionality.
Structural Reinforcement for Safety: Reinforcing the masonry, intermediate floors, and foundations to ensure the building’s structural integrity and earthquake resistance, ensuring long-term safety.

Sustainability in the project

Energy Efficiency and Thermal Insulation
• Modern insulation in the roof and attic expansions, improving energy efficiency, reducing heat loss, and lowering long-term heating and cooling energy consumption.
Adaptive Reuse of Existing Building
• The renovation and adaptive reuse of an existing historic building instead of demolishing it aligns with sustainable construction practices.
Minimized Construction Waste
• By strengthening and preserving the original structure, the project avoided extensive demolition, minimizing waste during the renovation process.
Integration of Natural Lighting
• The design likely optimized natural light through roof design, skylights, or light wells, reducing the need for artificial lighting and lowering energy consumption.