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Bridging an Architectural Gap

Monochrome apartment building lends itself to multiple styles

Greencoat Case Study Apr18 1

In recent years, the Swedish town of Uppsala has experienced a surge in growth. New buildings and districts have emerged, and older areas of the town have been revitalized. In some cases, the new growth has posed an architectural challenge, with buildings featuring different scales and approaches coming in contact with each other.

One good example of this is in the new district of Rosendal. Here, one side of the area consists of buildings designed with strong urbanism in mind and five or more stories. On the other side are buildings with a significant small-town character.

When a new apartment building was planned to be built right in between the two, architect Rahel Belatchew from Belatchew Arkitekter, Stockholm, was tasked with finding the right solution.

The challenge, according to Belatchew, was to “bridge the gap between two blocks with very different typologies.”

A Color-Coated Steel Solution

Belatchew’s solution was “Fjärilen” (the butterfly), a unique apartment building with a design that acts as an architectural hub by offering details that lend themselves well to both styles.

To achieve this extraordinary building, Belatchew chose to work with details like façade shifts as well as a varied roof. On the façade, a vertical panel design was used. The roof was inspired by traditional Swedish villas with a deep and high vaulted ceiling.

The city block around Fjärilen already contains buildings with many different materials and colors. Therefore, Belatchew wanted to create a uniform effect and limited herself to a single color and one material on both the roof and façades. In addition, a major goal was to choose building materials that have a low impact on the environment. Her decision was to use the color-coated steel GreenCoat PLX Pro BT, from SSAB, Borlänge.

“We wanted a monochrome building with a single material on the roof and façade,” says Belatchew. “Steel proved to be ideal for that purpose. The product has proven to be very reliable, giving us a very satisfactory finish without any buckles.”

Bio-Based Technology Coating

Well-known among tinsmiths and metal roofers for its easy hand forming and long color retention, GreenCoat PLX Pro BT also features a bio-based technology (BT) coating with a substantial portion of Swedish rapeseed oil instead of fossil-based oils, which are traditionally used. The unique, patented BT solution by SSAB reduces a building’s environmental footprint significantly.

In addition, GreenCoat PLX Pro BT is highly resistant to corrosion, ultraviolet (UV) radiation as well as scratches.

During the project, a very close dialogue was established between the architect, SSAB and the tinsmith company, Erikssons Plåt & Kopparslageri AB, Avesta, Sweden. With the help of many GreenCoat color samples, a unique shade of yellow was chosen.

“We spent some time looking for the right yellow tint. The Harvest Yellow color is bright and warm at the same time,” says Belatchew. 

The installation went smoothly and thanks to the very low thermal expansion of steel, the result is a clean look without buckling or deformation.

Nominated Design

For its striking, well-composed look and smart use of material, Fjärilen has caught the eye of many in the world of architecture. It has also been shortlisted for the Swedish Building Award 2017 (Stålbyggnadspriset 2017), which is awarded to a construction project that uses steel in an innovative, sustainable and architecturally appealing way. The aim is to encourage efficient use of steel in construction and give rise to new ideas and inspirational solutions.

Robert Moskowitz is with Confetti AB in Borlänge, Sweden. SSAB is a Borlänge and a Moon Township, Pa.-based steel company that offers value-added products and services. To learn more, go to