The intermediate floors of the steel-frame building were realised using Ruukki’s Kvantti floor slabs and the bathrooms are prefabricated space elements. The drains of the wet spaces (kitchens and bathrooms) were run in the installation space provided in the Kvantti floor slab and the columns and beams of the steel frame were mounted inside the stud walls between the apartments. The main façade cladding material is coated corrugated steel sheet.

Dry construction methods

The objective of the building project was to improve the technical quality of construction by utilising dry construction methods, as well as to produce information about the costs and schedules of dry construction methods versus conventional in-situ building.

Two identical building masses were built on the lot, one on a steel frame and the other on a traditional concrete frame. The concrete building has a conventional hollow-core slab floor and the wet spaces were built on the site, whereas the intermediate floors of the steel frame building were realised using Ruukki's Kvantti floor slabs and the wet spaces are prefabricated space elements. The drains of the wet spaces were run in the installation space provided in the Ruukki's Kvantti floor slab and the columns and beams of the steel frame were mounted inside the stud walls between the apartments. The main façade cladding material is coated corrugated steel sheet and the roof is a monopitch roof with felt roofing.

Variation possibilities

The studied dry construction system together with the installation floor opens up new possibilities for the design of apartments in high-rise buildings. The apartments are much more modifiable, with different layout solutions on the floors, and the location of water supply points and drains, openings in the external walls and partition walls can be chosen freely. This is the first residential high-rise building realised using the dry construction system in Finland.

Gallery access building of steel construction

The building is a four-storey gallery access building with one heated stair hall. The balconies and the galleries open up in the same direction. The idea of combining entrances with balconies is to create a more lively entrance atmosphere and to increase interaction and thereby promote community spirit.

The balconies and the galleries act as an active, constantly changing façade of the building.

The balconies and the galleries are structures based on galvanised steel pipe columns and concrete slabs.

Efficient, spacious interiors

The design objective has been fresh and unprejudiced residential architecture. Special attention has been paid to the details of the steel façades. As a result, the exterior is sophisticated and refined.

The starting point in the design of the apartments has been to provide efficient, "livable" space. Unnecessary corridor space has been eliminated in the apartments, focusing on effective space utilisation and a new, more spacious appearance. The means to achieve this include combining the entrance with the balcony and the entrance opening directly to the lounge space.

Floor area: 2,735 m²
Total area: 3,161 m²
Volume: 9,894 m³
Number of apartments: 48

Key information

Number of storeys	4
New-build home

Location of steel solutions

Balcony
Beams
Columns
External wall
Facade
Floor
Foundation
Internal wall
Light steel sections

Types of steel used in the building

Long carbon steel
Metallic coated flat carbon steel
Organic coated flat carbon steel

Housing Company Hellinniitty, Oulu, Finland