The Lyyra quarter currently under construction will be a new landmark in the district of Kallio in Helsinki, Finland. The block rising above the Hakaniemi metro station will have new cafes, restaurants and services, a hotel, apartments, and more than 7,000 m² of office space. Lyyra will be completed in stages from 2023–2024 and it is built with Peikko's DELTABEAM® composite frame.
The Lyyra quarter, owned by Ylva, the student union of the University of Helsinki, is being built to replace the technically and functionally outdated office and administrative buildings on site. The first construction phase completed Lyyra’s office and retail building, and the second phase consists of a hotel and apartments. The main contractor of the project, Haahtela, acts on behalf of Ylva, and Ramboll Finland Oy is responsible for the structural design. Lyyra's architects are Cederqvist & Jäntti Arkkitehdit Oy and the ARCO Architecture Company.
Visible buildings, challenging structures
Peikko was responsible for the delivery of Lyyra's steel parts, such as columns, DELTABEAM® Composite Beams, and PETRA® Slab Hangers. In addition, there is an open space in the maintenance yard of the office and retail building supported by an exceptional jumbo truss. The unique truss weighs more than 30 tons and crosses the entire maintenance area. It has a span of 22 meters and a height of four meters, and it transfers loads to the foundations from a height of eight floors.
"New solutions offer versatile opportunities for future steel construction, the jumbo truss being only one example," notes Peikko Finland's Business Manager Juuso Salonen, whose role has entailed involvement with DELTABEAM® and DELTABEAM® Frame.
The façade of Lyyra's buildings is spectacular but structurally challenging - the sharp pointed corners built on steel beams are Lyyra's best distinguishing feature. Inclined walls, long spans, and large window wall lines require special solutions, and, for example, steel frames are used instead of traditional solutions. The steel-framed restaurant area and the roof terrace on the top floor of the office building also challenged the structural design.
The DELTABEAM® composite frame utilizes the available space in two ways. Thanks to the slim floor structure, it is possible to increase the height of the room or build several floors up to a certain height. Composite columns take up very little floor space and leave larger amounts of space available than other construction methods.
”Lyyra is an ideal example of future construction; the space available will define the structures and solutions used. With innovations and out-of-the-box ideas, we are moving towards a more sustainable construction,” notes Salonen.
"The project benefitted hugely from the shared data model; it makes the modeling a whole lot easier and helps with the problematic details."
A shared data model offers synergy benefits
Lyyra won a prestigious honor at Finland’s 2023 Tekla BIM Awards. One of the special features of the design was that Peikko was inside of the other organization’s Tekla Model Sharing data model. Data models help the designers to communicate throughout the project. In the shared model, each party participating in the design immediately sees the level of readiness of other phases and can proceed accordingly. The cloud-based platforms have further enabled data model coordination.
“The modeling work of Lyyra was time-consuming with plenty of precise details of complex shapes and narrow space. The project benefitted hugely from the shared data model; it makes the modeling a whole lot easier and helps with the problematic details,” describes Timo Sihvola, Peikko Finland’s Modeler in charge of Lyyra’s DELTABEAM® Composite Beams.
"Exporting data models and drawings to the same application and linking them together meant a lot; the design would have been almost impossible without full-scale modeling of HVAC, structure, and architecture," explains Juuso Salonen.
Environmental friendliness throughout the construction and use
Responsibility is at the core of the project. The carbon footprint of Lyyra's life cycle has been estimated, and it will be reduced, for example, by using biogas as a form of heating, by looking for alternative raw materials, and by increasing energy efficiency. There will be solar panels and a green roof. The Lyyra project aims for a recycling rate of 95 percent of the demolition material.
Lyyra has applied for LEED Platinum certification, and in addition, the facilities are aiming to be approved to use class A, the highest possible energy class, by the regulating body of the Finnish Ministry of the Environment. Lyyra participates in the Inclusive Site project, which is one of the pilot projects of the OECD's Business 4 Inclusive Growth network.
One way to increase the environmental friendliness of a building is to make it flexible so that the structures can be easily modified for new uses throughout the building's life cycle. The slim floor structure of the DELTABEAM® composite frame enables the flexible design of floor plans. Furthermore, the second phase of the project is built with DELTABEAM® Green, which makes the carbon footprint of the site even lower. The carbon footprint of DELTABEAM® Green is approximately 50% smaller compared to conventional steel structures. In accordance with a more environmentally friendly operating model, more than 90% of the material is recycled, the electricity used in the production is renewable, and transportation is organized in an environmentally wise manner.
Logistics plays an important role
The hybrid project containing several different functions has required a lot of precision for project coordination. Placing a large building complex in the city center required careful coordination between the design and the demanding construction environment.
In the densely built and bustling center of Helsinki, new construction is challenging. The movement of large-scale components must be scheduled outside of peak times, and storing parts on a restricted construction site is not possible. Carefully planned punctual deliveries and intermediate storage ensured that all parts were delivered exactly when they were needed.
Lyyra, the quarter of science and economy, is built with the values of sustainable development and seamless cooperation.
This article has been originally published in Connections 2023 customer magazine. You can find more Peikko's customer magazines here: Connections customer magazine
