The Plus Alpha window provides “alpha space” that can function as an indoor balcony, and also pleasant indoor air, without having to open the door, thanks to the ventilation system on the top of the windowsill connected to the area that extends from the windowsill. It has addressed the issue of outdoor air conditioner units and various attached structures that have an ill effect on the building’s exterior and safety by offering a unified design. In addition to hidden frame and glass fence were due to be completed minimalism.