Hopealaakso daycare centre

The Hopealaakso daycare centre uses wood for many purposes, and the end result feels natural both inside and outside. When selecting materials, the genuine feel of the material, its patina, and ease of maintenance were the main deciding factors. The daycare centre won the 2021 Wood Award.

Read the article in Finnish: Hopealaakson päiväkoti

The Hopealaakso daycare centre is located in Kruunuvuorenranta, Helsinki. The two-storey building has a wide, uniform roof and a peaceful facade that borders the street and conceals the series of village-like meandering spaces indoors. A garden-like yard surrounds the building, giving it a pleasant frame.

The interior design makes use of indoor windows and glass walls, which open up interesting interior views between the spaces. Skylight areas are scattered across the building to offer more views between storeys.

With room for 210 children, there are a total of seven functional areas on the two floors. The ground floor has a series of connected entryways that people use to access the facility. An elevator and an internal staircase enable access to the functional areas on the first floor. Designed as a flexible open space, the uncomplicated shapes of the functional areas support the activities of small groups of different sizes. There are no corridors, and the spaces can be connected to each other because all partitioning walls are mobile.

The common areas are split between the two floors. A hall for evening events is on the ground floor and has a private entrance. A multipurpose space and workshop are centrally located on the first floor. Both floors have cafeterias. The staff offices and workspaces are centrally located on the first floor.

The entire space is designed to be accessible and ergonomic. All the ceilings have noise dampening materials as does the wall cladding, and the floors have coating that absorbs sound. Separated into its own complex, the indoor facilities of the neighbouring sports park are also tucked under the daycare centre’s roof.

Technical solutions

The building has a pile foundation and a ventilated concrete subfloor. CLT elements have been used for the load-bearing exterior and stairwell walls, with these structures being mostly left visible. The intermediate floor is a CLT/concrete composite structure (140 mm + 140 mm) mounted on steel beams, for perhaps the first time in Finland. The long spans enabled by this composite structure meant that ceiling beams could be left out, leaving more space for the building services. The roof structure is a load-bearing CLT slab with a wooden truss.

The building has a P2 fire class. The fire compartments are based on each room’s intended use. The daycare centre’s functional facilities on the ground and 1st floors belong to the same fire compartment, creating the building’s largest fire component at approximately 1890 m². The stairwells, attic, social space, sprinkler centre and storage facilities are all in their own fire compartments. The heat distribution room and the main electrical centre share a fire compartment. The attic (1516 m²) and the roof structure cavities are divided into 400 m² compartments. The foundation floor cavities are divided into 400 m² compartments if the space’s surfaces do not meet the requirements of category D-s2, d2 (small exceptions are allowed). Fire safety requirements for 1 and 2 storey buildings have been relaxed in Finland since the project was designed.

The building’s two separate exits face in opposite directions. There are a number of other doors on the ground floor that lead directly out of the building. The time to exit the build was calculated at the site to ensure the design complied with safety requirements. As called for by the Finnish RTS classification, a conditions simulation was also conducted at the site, leading to cooling being added to the air conditioning. The daycare centre is open all year round.

All ceiling surfaces have dampening materials, and the HVAC and other equipment is hidden behind acoustic panels. The ceiling in the lounge also has insulation. The floors have a coating that absorbs impact sounds, and the wall cladding will use sound absorbent material. Thanks to the excellent acoustics, it was possible to leave the wood surface visible and keep the echoes and other sounds in the light shafts under control. In CLT walls, one side is exposed and the other side is clad with insulation and gypsum board.

CREDITS

KK-Palokonsultti Oy, a leading Finnish fire safety expert for wooden structures, joined Puuinfo in January 2022. KK-Palokonsultti’s project is also Supercell’s office building, Wood City.

Puurakentajat Group Oy is a Finnish group specializing in wood construction and wood technology, with experience in solid wood construction since 2006. Puurakentajat designs and builds ecologically sustainable and healthy detached houses, apartment buildings and schools and kindergartens, such as Lapinmäki daycare centre, Metsola daycare centre and Supercell’s office building, Wood City.