The APV range of roof ventilator can be glazed into roof glazing and sloping curtain wall. This system is thermally broken and can be glazed into or with, almost unlimited thickness of double glazed units. We have glazed these vents into our system up to a size of 1000mm wide x 2000mm deep. These vents can be structurally glazed and used as openable flat top rooflight/ access hatches, they can also be used as walk on vents. With a variety of chain openers, rack actuators and even gas struts these vents are practical. With the use of two gas struts and chain operator this is a cheaper option of opening ventilator rather than the use of two motors and a synchronisation box.