The VELUX Group asked the global consultancy Navigant to independently source and organise testing of 9 different roof window types from 4 different European manufacturers. The roof windows were bought at different dealers in Germany, Poland, United Kingdom and the Netherlands, during different periods and the roof windows are thereby considered to be representative of what is available to customers in the market. The roof windows were first tested at ift Rosenheim in Germany and thereafter samples of the roof windows was sent for control testing at Centrum Stavebního Inženýrství a.s. (CSI) in the Czech Republic. Both institutes are notified institutes for testing of roof windows. The tests were carried out in accordance with the European standard for testing of Uw-values for roof windows (EN ISO 12567-2) using the reference size and the roof windows were installed in the test boxes in compliance with the respective manufacturers’ guidelines. We believe that the test results presented by the research institutes give a full and trustworthy picture of the tested products’ actual Uw-value performance.
The VELUX Group asked the global consultancy Navigant to independently source and organise testing of 9 different roof window types from 4 different European manufacturers. The roof windows were bought at different dealers in Germany, Poland, United Kingdom and the Netherlands, during different periods and the roof windows are thereby considered to be representative of what is available to customers in the market. The roof windows were first tested at ift Rosenheim in Germany and thereafter samples of the roof windows was sent for control testing at Centrum Stavebního Inženýrství a.s. (CSI) in the Czech Republic. Both institutes are notified institutes for testing of roof windows. The tests were carried out in accordance with the European standard for testing of Uw-values for roof windows (EN ISO 12567-2) using the reference size and the roof windows were installed in the test boxes in compliance with the respective manufacturers’ guidelines. We believe that the test results presented by the research institutes give a full and trustworthy picture of the tested products’ actual Uw-value performance.