The area of wooden windows hardware is largely controlled by four main companies: Roto, Siegenia, Maco and Winkhaus. M SORA uses Roto systems. Each of them offers a Tilt&Turn system, which can be either standard (visible) or concealed, as well as a hardware system for larger and heavier casements. The table shows the data of individual manufacturers and the maximum permissible weight of the casement permitted by their systems.
What does this mean in practice? Most of the weight of the window casement is represented by thermally insulated glass. 1 m2 of glass with a thickness of 1 mm weighs 2.5 kg which means 30 kg/m2 for standard triple insulated glass unit with three 4 mm glasses. If the window has dimensions of 1200 mm × 1400 mm, the weight of the casement is approximately 50 kg whereas the casement of the balcony door with dimensions of 1000 mm × 2300 mm is 70 kg. Both are fully in line with the restrictions for both visible and concealed hardware systems. If you decide for a larger balcony door with dimensions of 1200 mm × 3000 mm and laminated outer glass, a glass with a thickness of 6 mm or laminated glass made of two 5 mm glasses (e.g. 55.2) must be used. This would mean that the weight of the casement is about 200 kg, which means that special hardware are required. Window sizes therefore significantly affect the weight of the window casement and, consequently, the type of hardware system, and, last but not least, the price of the window.
