Finnish architectural studio Kivinen Rusanen Architects has completed the Tammisto Electricity Substation in Vantaa, a city in southern Finland (around 20 kilometers from Helsinki). This substation has served the Helsinki metropolitan area as a central power grid hub for many decades and its older systems required modernization. The studio’s approach provides an urban infrastructural facility with an architectural quality; the use of custom-made water-struck bricks laid in different masonry patterns imbues the substation with a sense of warmth and depth.
“The architectural goal was to give a unified appearance to the new and newly improved buildings and structures on the site,” says Kivinen Rusanen Architects. The site’s oldest structure is a former protected substation designed in 1947 by Finnish architect Aarne Ervi. The design for the new substation building harmonizes with Ervi’s design: the former substation has a low and long structure with a tall transformer tower at one end, gabled roofs, and ornate red brick facades — it is now used as an office building. The new substation’s facades feature water-struck bricks (a method that uses water to remove the brick from its mold) with varied warm tones and textures. Kivinen Rusanen connected the new substation’s architecture to its erstwhile counterpart through the building’s scale, massing, and facade materials. It is also aligned with an adjacent residential area's scale and fabric.
The Aarne Ervi-designed former substation is on the left:
“The old substation's two-part composition inspired the triangular cuts in the new building's mass,” says Kivinen Rusanen. “The building is divided lengthwise into three different sections defined by these cuts.” Access is provided to the substation’s facilities at either end; the longer central section houses the main processing equipment and cable rooms. The building features a two-story layout with serving spaces on the ground floor and the main equipment room and control room on the first floor. Its total floor area is 1,705 square meters (18,353 square feet).
The water-struck bricks are laid in four different masonry patterns that highlight the substation’s massing and its spatial arrangement. To complete the four masonry patterns across various parts of the building, thirteen different types of custom-made brick were needed. “Detailed 3D models of the brick facades were used to produce drawings for each type of brick and the supplier made the necessary molds for all of them,” explains Kivinen Rusanen.
The building’s frame is constructed using prefabricated concrete and its double-skin facades are supported by a steel frame set in the cavity. The substation’s north and south sections receive natural light through double-skin walls composed of lattice brickwork and full-height glass curtain walls with approximately a meter (three feet) of space between the two. The central section is windowless, however the main equipment room receives indirect natural light through the spaces at either end.
Kivinen Rusanen Architects also upgraded two concrete transformer bunkers built in the 1980s. Their facades were treated with an “Umbra color patination”: this is a chemical coloring process in which dye-forming reagents are absorbed into the surface of the concrete — reacting with the cement, they form a reddish-brown surface that resembles a rust color. The effect ensures that the site’s different buildings have a warm, unified appearance.
“The Tammisto Electricity Substation project seeks to give an architectural image to sustainable urban infrastructure development,” says Kivinen Rusanen. “It contributes to society's electrification, provides a reliable power supply, and aims to improve the aesthetic and cultural integrity of the site and the surrounding landscape.”
