Horizontally pivoting blades (glass, timber or aluminium) are mounted in a frame and provide almost unlimited adjustment control, for gaining the maximum amount of airflow through the window.
Louvres are an excellent option when positioned in high or hard to reach openings, with the powered option of being able to operate the window via wall switch or even an app on your smart phone, with the ability to open and close the window based on the time or temperature, with more options available.
