Originally posted by Alji:

That will work fine, though the top will weather and look gray after a while.

just to be clear, i already have a fully funtional roof. it's 50m off the ground at the center and goes all the way down to 12m above ground at the edge. it's a 152m x 152m continuous roof, like a very flat 4 sided pyramid. i'm talking about adding more roofs under the current roof, so nothing will weather.