Are you living in a big city and are homeless?
It's not the roof the roof that will kill you, but the pointy things on the ground waiting to impale you.
If you have a flat roof.
What happened to your sofa...
only at your own Risk
It is not safe to sleep on a roof. Rather, it is super dangerous and scary. A bear could easily climb up that tree that is growing next to the building and maul you or rip off your hands or brutally rape you. An eagle could swoop down and scratch out your eyes with its terrible talons and feed your guts to its babies. A troop of bloodthirsty apes could descend on you and steal your Kit-Kat. You do not want to sleep on a roof.
Dont fall down though.
Just dont roll off
Not during a thunderstorm with tin foil on your head to block out Alien sensing devices...
if its your house roof yea, but remember the bugs, birds, the scorpions, the centapeads, the parasites, the guy that wants to rape you, and the witches that can take you away.... other wise its preaty safe ^.^