concrete and glass interplay upon kn global seoul headquarters’ facade by zaira

ZAIRA designs KN GLOBAL Headquarters in Seoul

The KN GLOBAL Headquarters by ZAIRA Architects & Engineers is situated on a trapezoidal plot at the southern end of Gwangjin Bridge in Seoul, overlooking the Han River and Achasan Mountain. Located on a busy street known as ‘Cheonho-dong Tool Street,’ the building’s unique positioning on a sloped site with a 3.6-meter elevation difference allows for convenient underground parking without additional excavation, minimizing both construction time and cost.

Designed as an office building for a leading civil construction firm specializing in Tunnel Boring Machine (TBM) technology, the structure represents the company’s unique values through architectural form and materiality. While intended as a functional office space, flexibility for potential future uses was integrated into the design to accommodate the company’s evolving needs. ZAIRA Architects prioritized architectural alignment with the client’s identity, incorporating elements that symbolize the firm’s engineering expertise.

all images by Kim Jongoh

concrete lining technique informs the core frame

Drawing from ‘concrete lining’—a concrete structure installed on the innermost layer during tunnel construction—ZAIRA Architects translated this concept into an exposed concrete design that forms the core structural and aesthetic framework. This smooth, 450mm-thick concrete lining begins at ground level and continues through floors, walls, and ceilings, creating a cohesive spatial experience that mimics the layered depth of a tunnel cross-section. The exterior facade, derived from this layering, embodies a symbolic tunnel-like visual, which connects to the company’s industrial roots.

The building’s program accommodates parking in the basement with access from the rear, while the main entrance on the first floor opens into a public café. The second floor serves as an exhibition area, and the third to sixth floors house office and meeting spaces. Adaptations in the concrete lining across floors allow for optimal responses to sunlight, views, and functional requirements, creating dynamic shifts in both interior layouts and external form. These variations, achieved through reversing the concrete lining’s direction, add visual depth while maintaining the unified structural motif. The design was realized through a combination of advanced construction techniques, including flat slab structures, post-tensioning, gang form walls, steel and reinforced concrete columns, and exposed concrete finishes, ensuring structural efficiency and alignment with the raw aesthetic. Interior spaces feature exposed facilities and lighting, emphasizing the functional clarity that reflects the firm’s engineering-focused identity.

‘concrete lining’ inspired the exposed concrete design, symbolizing KN GLOBAL’s engineering focus

KN GLOBAL Headquarters by ZAIRA Architects overlooks Seoul’s Han River and Achasan Mountain

the exposed concrete structure flows through floors, walls, and ceilings, creating a cohesive spatial experience