A window with an electric actuator holds the sash firmly in position. However, it is not automatically as tight and burglar-resistant as a window with a locked fitting. Whether that is enough depends on where the window is located. This guide explains what matters for tightness, burglary protection and power failure, and when an additional locking actuator makes sense.
In brief: A window actuator holds the sash in position but does not replace a lock. For skylights, roof windows and high-level windows the actuator alone is usually sufficient. For reachable windows, for example on the ground floor, an additional locking actuator such as the VS-VA 600 is recommended for better tightness and burglary resistance.
Is a window with an actuator tight?
When closing, the actuator pulls the sash into the seal with its pulling force. For small and medium sashes, this usually provides good tightness. For large sashes, however, the actuator presses the sash at only one point. The seal may then be pressed less firmly at the corners.
The solution is a Locking drive VS-VA 600. It is combined with the chain or spindle actuator and locks the sash via the fitting after closing. This improves tightness and increases burglar resistance. For wide sashes, two synchronised actuators also help, see tandem operation.
How burglar-resistant is a motorised window?
An actuator holds the window in the position it is in. However, it does not replace a lock. What matters is whether the window can be reached from outside:
| Window location | Recommendation |
|---|---|
| Fanlight, roof window, skylight dome, high facade window | Actuator alone is usually sufficient |
| Ground floor, window next to a balcony or canopy | Combine actuator with locking actuator |
| Window that should stay open at night | Keep the opening width small, see below |
Leaving it tilted at night: what to consider
- Gap ventilation instead of wide open: A small gap is often enough for night ventilation. Many actuators have an adjustable stroke, which lets you limit the opening width, see Opening width.
- Close automatically in bad weather: A Rain sensor or wind-rain sensor closes the window when the weather changes.
- Time control: Windows can close automatically in the morning before anyone leaves the room, see Ventilation control.
- Insurance: How an open or tilted window is assessed in the event of a burglary is governed by your insurance contract. If in doubt, ask your insurer.
What happens in a power failure?
Without power, the actuator stops where it is. A closed window stays closed, an open one stays open. The rain sensor cannot close the window without power either. Keep this in mind if you leave windows open while away.
Smoke and heat exhaust is different: an approved SHEV control panel has an emergency power supply so that the windows open even without mains power in the event of fire. Find out more in the guide SHEV and daily ventilation.
Safety for people: anti-trap protection
A window actuator works with considerable force. According to our installation instructions, windows installed below a height of 2.5 m must be equipped with reliable anti-trap protection. In public areas, an additional safety sensor is provided. Controls should be positioned so that the window can be seen while it moves.
Frequently asked questions
Can I retrofit a locking actuator?
Often yes, if the window fitting is suitable and there is enough space on the profile. Send us a photo of the fitting and we will check.
Can I close the window by hand during a power failure?
That depends on the actuator and the window. Clarify this before installation, especially for windows that are often open.
Does the actuator make the window less secure than a normal handle?
Not for high windows, because they can hardly be reached from outside. For accessible windows, a locking actuator should take over the role of the handle.
Consultation
Would you like to motorise an accessible window and lock it securely? Send us dimensions and photos of the window and fitting via the Contact form. We will recommend the right combination of actuator and lock.