With smartwin windows and SWISSPACER ULTIMATE spacer bars: the new “Elmeskolan” in the IKEA-dominated city of Älmhult in southern Sweden
It has a heat requirement of 9 kWh/m² and with 10,300 m² of usable space it is the biggest passive house school in Sweden. The Elmeskolan in Älmhult was built according to the international passive house standard. The windows come from the Latvian company “i2 Factory”, which is part of the smartwin network – an association of 15 medium-sized windows manufacturers across 10 European countries. Inside the insulating glass, SWISSPACER ULTIMATE spacer bars ensure maximum energy efficiency and a high level of comfort.
“Älmhult is growing rapidly. That is why we had to build a new school for 800 children,” explains Lars Lund, project manager for the municipality of Älmhult. The two-storey building, which was finished in late 2017, houses a traditional school, an English-speaking international school and an international kindergarten. The first IKEA furniture store opened in Älmhult in 1958 and it is here that one of IKEA's head offices is located. Employees from 53 nations are employed here. Lars Lund: “Several of the students at the international school have parents who work for IKEA and will stay here for a few years.”
“The political responsibilities in Älmhult wanted a school with low energy costs,” says Lars Lund. The temperature in Elmeskolan is around 21 °C. A geothermal plant was built for warm water and heating; it uses 20 geothermal probes to warm the air for eight ventilation systems. The building shell has U-values of 0.06-0.13 W/m²K; the exterior walls are a sandwich construction of concrete and PIR insulation that is 255-295 mm thick. “For a passive house in the cold Swedish climate, we need windows in energy efficiency class A. They don’t make those in Sweden,” says the architect and structural engineer Simone Kreutzer from the IG Passivhus Sverige AB. She advises on, supervises and coordinates the construction of passive houses like the one in Elmeskolan. That is why smartwin windows from Latvian company “i2 Factory” were used. The smartwin windows are certified by the Passive House Institute in Darmstadt and are developed by the German company pro Passivehausfenster GmbH. They have a reference size of 123 x 148 cm and a U-value of 0.62 W/m²K. They are produced regionally in 10 European countries by window manufacturers in the smartwin network.
“We use thin frames to achieve greater solar gains,” says Franz Freundorfer from pro Passivhausfenster GmbH. The depth of the frame in wooden windows with aluminium profiles is over 106 mm, whereas it drops to 48 mm with triple glazing and a warm edge spacer bar. “SWISSPACER spacer bars are our top choice. The Psi values of SWISSPACER ULTIMATE are the best in the world, they are durable and the sealant is not permeable to gas and water vapour,” stresses Freundorfer. “In addition, SWISSPACER spacer bars can be used to keep the temperature on the inside at the edge of the glass 16-17 °C – high enough that no condensation is formed”, adds Simone Kreutzer.
“Passive houses built according to the international standard are still uncommon in Sweden,” says Simone Kreutzer: “but in schools and kindergartens there is currently a passive house boom.” Demand-based ventilation, as required in passive house buildings, had been standard in Swedish buildings for 25 years now, she says: “In addition, passive house buildings are planned to be more compact and functional. Therefore, the building costs are lower in particular when it comes to bigger buildings. As are the operating costs, as the heat requirements are reduced by up to 75%.”
Different sized windows with colourful frames adorn the school's exterior; on the inside it looks bright. That is thanks to the lighting concept, with the size and number of windows optimised in terms of their direction and use, and plenty of glass on the inside. Glass doors and elements in the walls, including between the classrooms, allow light to reach into the corners and corridors. This saves not only lighting costs. “It creates a feeling of openness, comfort and security,” says the architect Mikael Gustafsson from Horisont Arkitekter AB in Malmö. He was involved in the project from planning to completion and his design gave the school extra flexibility: the building is divided into units for 50 children and young people, consisting of classrooms, learning areas, free time and group areas. Sliding wall panels allow bigger rooms to be made into smaller ones – and vice versa – as required. That means Elmeskolan is fit for the future in terms of energy – and with the flexible room division it is also open to the educational concepts of the future.