What is an actuator?
A window actuator is a type of motor for moving or controlling a mechanism or system. It is operated by a source of energy, usually an electric current, hydraulic fluid pressure, or pneumatic pressure.
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.
What window actuator do I need?
A variety of window actuators are available for different window types depending on what the required free area is:
 | Top hung outward opening windowMost often controlled by a chain actuator, or for larger windows, a folding arm is a reliable option. |
 | Side hung windowOnce again a chain drive would be suitable subject to being able to deliver the required free area. Otherwise, a slit actuator or folding arm may be employed. |
 | Bottom hung windowMost often controlled by a chain actuator, or for larger windows, a folding arm is a reliable option. |
 | Rising sash windowIt 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. |
Need help deciding which window actuator you need?
Try our Actuator Calculator which displays all of the available actuators based on your specific requirements. Additionally, you can read more about the different types of actuators and their benefits in our blog.
Under the Construction Products Regulations (CPR) it is a legal requirement to use only certified products for smoke ventilation. It is the responsibility of the installer to ensure installations meet the relevant standards. For more information see SCS Group’s Technical Bulletin here.
