A louvre window having: a frame, the frame having a head, a sill and at least two jambs; a drive bar located in one or both of the jambs that is movable by a handle; a plurality of blades located within the frame and connected to the drive bar by a pivot drive connector, such that movement of the drive bar urges the blades to pivot, each blade having: a first windowpane attached to the blade; and a second windowpane attached to the blade, wherein operation of the handle causes movement of the blades between an open position and a closed position, wherein in the open position the first windowpanes are aligned to form a barrier against airflow and the second windowpanes are aligned to form a barrier against airflow and in the closed position the first windowpanes are pivoted out of alignment to allow airflow and the second windowpanes are pivoted out of alignment to allow airflow.