A window restrictor (Dutch “kierstandhouder”) is a piece of door and window hardware that lets you fix a window or door on a narrow, locked gap. This way you can ventilate while the window or door cannot simply open further. Through the narrow gap a burglar has to make more effort — and more noise — to get in, which makes it burglar-resistant.
How it works
- The hardware holds the window or door in a limited, locked ajar position
- Unlike an ordinary vent position, the gap does not fall shut and cannot be pushed open from outside
- There are versions with a recognised approval mark (such as SKG) that meet burglar-resistance requirements
Application
- Bedrooms — sleeping with the window safely ajar for night-time ventilation
- Front doors — opening the door on a gap to see who is there without fully unlocking it
- Ground floor and reachable windows — where a window left ajar would otherwise be vulnerable
Points to note
- Choose hardware with a recognised approval mark if security really matters; cheap restrictors offer little resistance
- Fit the hardware as specified into solid material; the strength also lies in the fixing
- Combine with good drainage: a window left ajar lets water in during driving rain
Related terms
- Door hardware
- Burglar-resistant
- Burglar-resistant hardware
- Window
- Anti core-pulling protection
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