Seven-storey CLT block built in less than a year

The block in CLT was built in Tampere, Finland and is designed for students. The project started in 2019 and construction began in June 2020, with the foundation poured and the ground floor built, also in concrete. The installation of CLT elements for the erection of the seven floors comprising 70 apartments started in November 2020 and the entire complex was handed over "turnkey" in May 2021.

Each building of the complex was built with a different type of material, the facades revealing this aspect

TOAS Kauppi is part of a five-building complex that borders Tampere University Hospital and Kauppi Sports Park. The residential buildings and an above-ground car park are located around a common green space, a kind of inner courtyard.

The idea of the architectural firm that designed the entire complex was that the exterior of the buildings would highlight the different construction solutions and building materials used. As a result, the buildings have facades made of materials such as handmade bricks, sanded plaster or metal grating. With facades made of larch wood, TOAS Kauppi completes the selection of materials.

The starting point was to design and construct a building that would meet the needs of the developer and fit into the urban landscape in a pleasing and sustainable way. Untreated planed larch, selected for cladding, is a way to present the building's structure while adding texture to the façade. The folded form of the facade gives residents views in different directions and gives the building a distinct and personal character.

TOAS Kauppi complex built for students

TOAS Kaupi has eight levels. The ground floor, built of concrete, houses a bike storage room with bike maintenance facilities, storage spaces, civil defence shelter, communal sauna and a laundry. The seven floors are built on CLT structure and house a total of 70 student apartments.

The choice of finishing materials for interiors took into account the requirements for fire resistance, sound insulation and long-term durability. These requirements were combined with the desire to leave as much wood as possible exposed. In the apartments, the surface of the CLT beams was treated with transparent fire retardant. The interior frames of the wooden and aluminium windows were lacquered with clear, semi-transparent varnish. In the corridors and stairwells, the wood of the CLT structures that form the apartments and make up the entire strength structure was also left exposed and finished with transparent protective materials.

The sound insulation design of the building took into account all nearby noise generators, including the noise from helicopters landing on the hospital helipad. The complex was to be inhabited by students and they needed quiet. Some of the exterior walls have been boarded inwards with three layers of plasterboard to ensure they meet sound level requirements. In addition, doors and windows were also selected for their acoustic properties.

In less than a year from the start of construction, the complex was handed over to the developer

The developer started the project in November 2019. To choose the most suitable option, a multidisciplinary team was put together to analyse the different solutions and options. From the outset, the aim was to combine architecture, in which wood was both a structural and aesthetic element, with functional technical solutions. The subsequent maintenance of the building played a key role in the decision making.

All those involved in the project have been involved in the decision making and design from the very beginning. The collaboration between architect, designer, developer and material and equipment suppliers was constructive and forward-looking. Work started on site in June 2020 with the foundation and ground floor being made of concrete. Installation of the CLT walls began in November 2020 and the site was handed over to the developer in May 2021.

Further information about the Tampere project can be found at here.