Helsinki, Ullanlinna

Renovation, Residential Building
Scope: 5,501 m²
Architect: Arkkitehtitoimisto Jani Prunnila Oy
Responsible Structural Designer: Anna-Kaisa Mero
Structural Design Project Manager: Anna-Kaisa Mero
Complexity: Demanding (Class V)

As Oy Grand Horizon is a residential apartment building by the sea in Helsinki’s Ullanlinna district, originally completed in 1925. Designed by Frosterus & Gripenberg Architects, the building is partially protected; however, no modifications were made to the protected structures during this renovation. The seven-story building includes a basement, attic, and a mixed structural frame with solid brick exterior walls.

Despite its long history, this comprehensive renovation, launched in 2022, was the first extensive repair project undertaken in the building’s lifetime. Nodetec was responsible for the structural design of the renovation.

Key Features of the Renovation:

• Complete renewal of building systems and wet areas.
• Apartment layout changes and new openings in load-bearing structures.
• Repair of beam-slab intermediate floors.
• Expansion of living and recreational spaces into the basement level.

Design Considerations:
Special attention was given to preserving the historically valuable interiors, improving acoustics between apartments, ensuring healthy indoor air quality, optimizing routes for building systems, and achieving high-quality surface finishes. Regular site visits were conducted to refine and update design solutions as needed.

Lähde: HS – Ari Veikko Peltonen

Lähde: Kuvaaja Pia Parepalo, Helsingin Kaupunginmuseo