As a space-saving alternative to the conventional French door, sliding doors are an excellent solution for large openings and allowing natural light into living spaces. The most important difference is the opening variant. Bifold doors can be moved to one side completely but due to this construction, they necessarily require a threshold. With a sliding patio door, you always have a fixed sash at one side but you can also use it to create a barrier-free passage. To balance any difference between the external and internal ground, a cill can be attached.