Stairwell ventilation can be achieved by automatically opening a window within the stairwell. As always this is subject to the minimum free area being achieved when calculated using the method in diagram C7 of Approved Document B.
It is recommended that bottom hinged outward opening windows are selected for efficient smoke evacuation, however this is not a requirement of ADB. Stairwell ventilators are more commonly used for replacing fresh air in a lobby extract system.
A variety of actuators are available for different window types depending on what the required free area is.
Rising sash window
It is possible to automate a vertical sash window using linear actuators. The slit actuator from Simon RWA is a neat and unobtrusive solution to such applications.
Top hung outward opening window
Side hung window
Bottom hung window
For more information on stairwell AOV systems, Easivent has written a pocket guide which you can download now!
Under the Construction Products Regulations (CPR) it is a legal requirement to use only certified products for smoke ventilation. For more information see SCS Group’s Technical Bulletin here.