While watching a video of a crazy person jumping around on buildings in some Asian country in a death-defying manner, I noticed these odd "safety" ledges outside, with nothing preventing you from falling down if you were crazy enough to exit a window from one of the apartments:


What is the purpose of this? If it's for washing the windows from the outside, isn't that horribly unsafe for anyone living in the apartments? And isn't there a standard way to wash windows/walls on a "flat" skyscraper from the outside by having a vertically moving thing? Which would be impossible with these weird ledges in place?

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    $\begingroup$ No. It is a feature of the building for the esthetic looks that serve no other function. You need to look at more buildings around the world. I am voting to close this post. $\endgroup$
    – r13
    Sep 3, 2021 at 14:25
  • $\begingroup$ @r13 I can't tell if you're being sarcastic or serious. $\endgroup$
    – B. Nikel
    Sep 3, 2021 at 14:27
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    $\begingroup$ How do you know that they are safety ledges? Or how do you know that they are for people falling? Maybe they are to catch items from falling out of a window and hitting a person on the ground. There are lots of options, so it would help your question if you supplied a reference to them being on buildings for safety. $\endgroup$
    – hazzey
    Sep 3, 2021 at 15:30
  • $\begingroup$ @hazzey I don't. That's why I used quotes. I didn't know what else to call them. And in your proposed scenario, they would still be "safety" ledges. $\endgroup$
    – B. Nikel
    Sep 3, 2021 at 15:40
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    $\begingroup$ I'm voting to close this question because the thought of someone parcouring about these ledges gives me vertigo. $\endgroup$
    – mart
    Sep 3, 2021 at 20:41

2 Answers 2


It might be a passive fire protection measure.

While the ceilings between floors are fire rated, fires can easily spread through the windows along the outside façade. (Coanda effect will pull the flames towards the building)


The ledges push the plume away from the building.



They may be part of architectural features. They can be an attempt to cover up some structural tie-beams or retrofit work ordered by the building authority.

Or they could be some kind of window awning to provide shading.

They certainly weren't designed for parkour heroes jumping around on them.


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