Bi-folding doors Bi-folding doors profile thickness 138 mm, thanks to innovative opening system consisting of sliding and folding doors, guarantee an amazing open space effect and provide a lot of sunlight. Doors are equipped with …, glazing packages up to 28 mm thick and a rebate gasket. They are resistant to extreme conditions – solar radiation in summer and low temperatures in winter. The surface of the window is secured with proper painting with environment-friendly TEKNOS paints and water based primers. We also offer a wide range of covering colours and visualizing the wood’s natural structure colouring varnishes. PROFILE vertical section horizontal sections scheme 3-0 schemat 2-2