Vertical Extension on Avenue Wendt: Innovative Residential Expansion in Genève

The Vertical Extension on Avenue Wendt in Genève, Switzerland, designed by Lacroix Chessex, exemplifies a thoughtful and contemporary approach to urban residential expansion. Completed in 2023, this two-floor vertical addition transforms a 1950s building into a modern, visually striking residence while harmoniously engaging with its urban context. Covering an area of 1,150 m², the project combines sustainable wooden construction, careful spatial planning, and panoramic views of the Alps and Jura mountains.

Contextual Integration and Architectural Vision

The site, adjacent to recently extended neighboring buildings, presented both a challenge and an opportunity. Unlike conventional solutions aimed at architectural continuity, Lacroix Chessex embraced a distinct architectural language. The project respects the original structure’s historical elements, such as the preserved eaves, using them as a design feature rather than erasing them to match neighboring renovations.

By maintaining the depth of the eaves, the architects created spacious continuous balconies that maximize natural light and provide residents with unobstructed views. The building’s crown is articulated by repeating the eaves horizontally, forming elegant strata that enhance its visual rhythm. This design approach offers a bold contrast to urban monotony, transforming a standard residential building into an iconic rooftop cabin-like structure.

Sustainable Wooden Structure and Materiality

A central feature of the vertical extension is its lightweight wooden structure, which emphasizes sustainability and material honesty. Exposed wooden floors, beams, and external extensions highlight the construction’s natural texture and craftsmanship. The facade integrates panel cladding, French windows, and loggias in two distinct layers, using a slightly darker wood to create depth and accentuate the new addition against the original building.

This material choice not only reflects eco-conscious design but also resonates with a nearby chalet, establishing a dialogue between urban density and vernacular architecture. The project challenges conventional city construction practices at a time when climate-conscious approaches are increasingly essential.

Thoughtful Spatial Organization

The vertical extension introduces adapted housing typologies tailored to the urban environment. Living areas are oriented toward the street, connecting residents to the city, while sleeping spaces face the courtyard and green spaces, ensuring privacy and tranquility. This thoughtful orientation enhances the quality of daily life, balancing urban vibrancy with peaceful residential retreat.

Technical and Collaborative Excellence

The project involved a multidisciplinary team to ensure structural integrity, environmental efficiency, and acoustic comfort. Key collaborators included:

• Civil Engineer: Moser Ingénierie
• Electrical Engineer: SRG Engineering SA
• Acoustic Engineer: Batj SA
• Environmental Engineer: Alterego Concept SA

This collaborative approach ensured that the Vertical Extension on Avenue Wendt achieves both aesthetic ambition and functional performance.

Redefining Urban Vertical Living

With its innovative design, sustainable material palette, and careful spatial planning, the Vertical Extension on Avenue Wendt exemplifies modern urban residential architecture. It transforms a modest 1950s building into a dynamic, visually engaging structure that respects its context while offering a fresh architectural perspective. This project stands as a testament to how thoughtful vertical expansions can enhance urban landscapes and redefine city living.

All photographs are works of  Olivier di Giambattista