UPM-Biofore-Magazine-2-2017-ENG

The Pudasjärvi comprehensive

school is the world’s largest school built from wood.

heart rates become more regular and stress levels are reduced. “The logs preserve the natural colour of the wood, so the building feels like a home or even a holiday house,” adds Lumme. The Pudasjärvi comprehensive school is the world’s largest school built from logs. The Log Campus is divided into four buildings, three of which are constructed entirely from logs. These three buildings house a primary school, a lower secondary school and an upper secondary school. The kitchen and emergency shelters are made of concrete. The estimated lifespan of the building is 150 years. Grabbing headlines worldwide The Log Campus has generated a great deal of interest both at home and abroad, attracting approximately 5,700 visitors to date. “About one third of Finland’s municipalities have sent their local policymakers to visit. The number of domestic visitors is diminishing, but international interest is still growing. We’ve had about 2000 foreign visitors,” says Lumme. In Finland, logs are becoming an increasingly popular construction material for schools, office buildings and retirement homes. Legislation and regulations governing energy efficiency are moving in a direction that supports the increased use of logs in the construction of public buildings.

Versatile plywood

Plywood is also a versatile construction material with typical end-uses in wall, floor and ceiling structures. “Plywood constructions are usually hidden under tapestries and coatings, so they are not visible to the user. This does not undermine the importance of plywood, as buildings need a durable, safe and healthy frame,” says Olli Wirén , Construction End UseManager at UPMPlywood. “Birch plywood creates a pleasing light surface that is ideal for both business premises and home interiors. On the other hand, spruce plywood is often chosen for its more prominent natural streaks, veins and knots – a visual trend that has been gaining ground lately, especially in Central Europe.” Light but strong In addition to homes and holiday houses, the use of wood is becoming increasingly common in the construc­ tion of public buildings such as kinder­ gartens and schools. In Finland, wood is used in approximately 40% of construction projects, whereas in

Europe the figure is only 4%. Plywood is manufactured by gluing several layers of wood veneer together crosswise. The layered structure evens out the natural inconsistencies of single veneers, making the plywood sheet exceptionally strong and consistent. A safe product All WISA® plywood products bear the CEmarking complying with the criteria of the European Union Construction Products Regulation. This means that the products are carefully defined as well as documented and are always inspected and validated by a third party. The EU has also set strict maximum values for the amount of formaldehyde permitted to evaporate into the air from wood sheets. Formaldehyde is a natural chemical compound that is commonly found in plants and trees. “For example, theWISA plywood products emit less than a tenth of the EU’s threshold limit for formaldehyde,” says Product Manager Riku Härkönen . Pudasjärvi comprehensive school is the world’s largest school built from logs.

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