Kulttuurikasarmi combines film and restaurant experiences under the same roof
Kulttuurikasami The story of Helsinki’s old bus station continued when the protected building was transformed into a vibrant entertainment and cultural centre with restaurant services. Sweco was responsible for the exceptionally demanding structural, HVAC, and electrical design, as well as moisture-management coordination.
In autumn 2023, the new entertainment and cultural centre Kulttuurikasarmi opened in the former Helsinki bus station. The building had stood vacant in the heart of the Lasipalatsi block until Ari Tolppanen, Chairman of the Board of Kulttuurikasarmi Oy and the driving force behind the project, envisioned a film centre.
“I walked past the building in 2015 and thought something should be done with it. The first idea that came to mind was, of course, a cinema,” Tolppanen recalls. His earlier film centre project, Nordia, which operated on Yrjönkatu until 2000, served as a model. “Given the location, the bus station offered even greater possibilities.”
Planning began in 2019 for underground cinema spaces. The concept later expanded to include event spaces on the top floor, a restaurant level at street level, and a glass pavilion supported by tie-columns and steel beams atop the courtyard roof.
“Kulttuurikasarmi took its final form based on detailed calculations and market analyses. In the end, it was probably built according to the 14th version of the plans,” Tolppanen says. Sweco was involved from the beginning. “We understood how crucial HVAC and electrical engineering, as well as the construction of the underground spaces, were to the final outcome. Sweco is a reliable partner.”
A 10-metre excavation beneath Kulttuurikasarmi
According to Sweco’s Department Manager Harri Makkonen, the site’s central location was exceptional. The design had to accommodate, for example, the potential future Pisararata commuter rail tunnel beneath the city centre. The renovation was extensive: “Only the protected exterior walls, the timber intermediate floors at the far end, and an old decommissioned stove casing remained.”
Sweco’s moisture-management coordinator supported the structural engineers in addressing challenges with the wooden intermediate floors, which were found to have rot and old fire damage during demolition.
“The structural engineer designed sealing details that allowed some elements to be safely retained,” says Sweco’s indoor air quality specialist Jonna Heinonen. Hazard surveys had already been conducted to support the design before construction began.
A roughly 10-metre-deep pit was excavated and blasted beneath the building. The old masonry exterior walls were extended underground with cast-in-place reinforced concrete. “During construction, the old exterior walls had to be supported with bored-pile towers and horizontal braces,” Makkonen explains. The roof was replaced with a lightweight structure supported by new steel frames, while the eaves height remained unchanged.
Indoor air quality ensured through careful concrete drying
Heinonen worked closely with structural designers and contractors to manage indoor air quality. The largest concrete slabs were about half a metre thick, and some were poured during winter, resulting in long calculated drying times.
“We supplemented the drying-time calculations with building physics simulations, and monitoring site conditions during construction was essential to ensure proper drying.”
Drying schedules were especially tight for the underground cinema slab. In some cases, drying was monitored weekly, allowing floor finishing to proceed in stages. The structures were also inspected during the warranty period.
“A year later, I conducted moisture measurements under the finishes in areas such as the cinema auditorium and foyer. The structures had dried and performed as expected,” Heinonen says. She also carried out final cleanliness inspections after project completion.
Building services installed without altering protected façades
All functions had to fit within approximately 4,000 square metres, requiring extensive coordination between steel structures and building services. “From a building-services perspective, no square metre is the same,” says Sweco’s Head of Electrical, Telecom, and Security Engineering Niklas Lind.
The City of Helsinki reviewed the visual impact of the design, and all technical systems were hidden from view. Ventilation, smoke-extraction fans, and other equipment were concealed within technical stacks resembling the building’s original chimneys.
The site includes several kitchens, and the cinemas and foyer feature DMX-controlled effect lighting. “The DALI-controlled lighting system supports around 60 different luminaires,” Lind notes.
Safety is ensured through access control, camera surveillance, and robbery-alarm systems. The fire-alarm system manages emergency lighting and underground auditorium technology and can automatically stop screenings if needed.
Energy simulations ensured comfort in the Glass Pavilion
Kulttuurikasarmi uses district heating and cooling, and all waste heat is recovered. Liquid-circulation heat recovery serves both the ventilation system and kitchen hoods. Energy simulations were used to verify indoor conditions, especially in the fully underground theatres and the Glass Pavilion, which heats up in summer.
“For the pavilion’s moisture management, we considered the inverted roof structures,” Heinonen explains. The thermal insulation layer was mechanically dried, and moisture levels in both the insulation and the cast floor were measured before finishing.
Tolppanen is pleased with the result: “The building works well, and the Glass Pavilion—challenging in terms of conditions—is warm in winter and cool in summer.”
Kulttuurikasarmi opened on 17 November 2023 and has been warmly received by visitors. “We added a new section that fits seamlessly with the 200-year-old building and introduced diverse functions across all three floors,” Tolppanen says. He considers the cinema viewing conditions ideal: thanks to the excavation, the auditoria are perfectly proportioned. “Once people visit, they tend to return—and our event spaces are also very popular.”