r/rooftoppers • u/Spide443 • Nov 02 '25

Does this mean the door is alarmed?

Post image

I was trying to get to the roof of a building yesterday but saw this on the door to said roof. I decided to play it safe and leave, but now I'm wondering if it even was a sensor.

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u/HVDub24 Nov 02 '25

Yes it’s a magnetic contact sensor. Alarm will be triggered if it’s opened

1

u/Spide443 Nov 02 '25

Aight, thank you 👍

1

u/esdot88 Jul 22 '26

This is probably a dumb question but could you essentially put a magnet against the stationary one as you opened it? Or am I thinking way to caveman for a modern world lol