Window alarms and awkward shaped windows

[Ceetee]

I bought my elderly mother some window alarms after she had a scare, however her windows are not flush so the sensor doesn’t come in to contact with the magnet, any easy suggestions for a novice?

 

[AC Power]

I would probably cut a piece of wood (paint to suit) sized accordingly to "build up" the wooden frame around the glass so as to be flush with the fixed frame in which it mates with.

This way, the magnet and the receiver/horn will evenly meet when the window closed.

 

[Ceetee]

Thank you, that’s exactly what I’ll do!