Details
The annex to the National Museum of Finland is a demanding example of specialist construction in the heart of Helsinki. Despite its high-quality architecture and technically demanding solutions, the new building has a 25% smaller carbon footprint than a conventional building.
The largest construction project in the National Museum’s more than 100-year history provides additional space for the museum’s renewed activities and is a unique example of specialist construction. SRV built an annex to the National Museum, completed in 1910, with some of its functions located underground.
The extensive construction work began in autumn 2023 and was completed in 2026. The developer was Senate Properties, which is responsible for government-owned premises. We implemented the project using Senate Properties’ spearhead alliance model, developed for particularly demanding construction projects.
Most of the annex is below ground
The new part of the National Museum was built on the museum’s existing site, where the annex connects to the historic main building. The annex has a floor area of approximately 5,900 square metres, of which around 600 square metres are above ground. The remaining premises are located underground on two levels.
The above-ground, bowl-shaped pavilion houses the entrance and restaurant facilities. The new exhibition and public spaces are located underground.
The National Museum annex is an architecturally ambitious and unique construction project designed by JKMM Architects. The visible pavilion above ground contains the most demanding element of the annex: its striking roof structure.
A demanding building with a smaller carbon footprint
Building services engineering plays a key role in the annex, ensuring the right conditions for the museum’s irreplaceable collections. Working in close cooperation with the client, the expertise of SRV’s building services engineering unit was instrumental in delivering this unique building.
Building services engineering also played a significant role in minimising the building’s environmental impact over its lifecycle. Low-carbon solutions were considered from the design stage onwards by comparing different alternatives in terms of total costs and lifecycle emissions.
The project also developed a hybrid system combining an exhaust air heat pump with air handling units, significantly improving heat recovery from ventilation and waste heat. The system helps to reduce the building’s carbon footprint by 25% compared with a conventional building, in line with Senate Properties’ target for new-build projects.
Major construction work on a compact site
The National Museum annex was built on a compact site in the middle of the busy residential blocks and routes of Etu-Töölö in Helsinki. To work within the constraints of the site, the project used one of Northern Europe’s most powerful tower cranes, capable of lifting ten-tonne steel beams over long distances directly into position.
Before construction began, 20,000 cubic metres of rock were excavated from the site. At the same time, we ensured the safety of the surrounding area and protected the treasures of the historic main building, including the Gallen-Kallela frescoes.
Two separate construction sites were also operating on the site at the same time, as space was needed for the major refurbishment of the National Museum’s main building. Cooperation between the two main contractors was seamless, earning particular praise from the client.
The project has been highly complex in terms of both structural engineering and detailing. The site team has succeeded in realising the architect’s vision and meeting the objectives set for the project by the client and user. This was made possible not only by the first-class professionals working on the site, but also by the excellent team spirit. The project was implemented using Senate Properties’ spearhead alliance model, which we have developed for our particularly demanding construction projects.
Jukka Lallo, Developer Manager, Senate Properties
When you build, build wisely
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