Is use of schools' rooftops a common thing in Japanese culture or just a cliché? In many manga and anime involving modern schools, there is a scene on or at least showing the rooftop of the building. It is a place students can freely go to, often depicted with having a bust-height railing along the edge and the typical 'small building' from which you leave the school building, often also having a ladder to get up (nonetheless being a popular 'hiding' or 'being alone' spot even without one).

I wanted to ask: is this one of many clichés about Japanese culture that appear throughout the whole media type, or are they a common thing in Japanese schools?
I am sorry, but they look like just a cliché....

From this Quora answer (yes Quora!):


  While many Japanese schools do have flat rooftops, they are usually off-limits and properly locked. So, eating your lunch on the roof or confessing your love at sunset up there... not gonna happen.


Source: Quora

Another source directly from our own Anime and Manga StackExchange: AM StackExchange

A quick Google search also reveals this (unfortunate) truth.