With Josko’s technically sophisticated Diamant 89 lift-and-slide door system which has been tested for tightness by Holzforschung Austria, even large glass panels are easy to open. Josko’s traditional lift-and-slide doors are available in all materials so they harmonise with your choice of window system. Diamant 89 is the traditional wood/aluminium lift-and-slide door. Josko's Diamant 89 lift-and-slide door had to pass many in-house tests and undergo further development before it was ready for the market. The persistence paid off. In the impermeability test conducted by Holzforschung Austria’s accredited test centre, the best results were achieved for resistance against air, driving rain and wind.
