Nowadays, there is a major concern of bird flu and bird droppings.
Since the 1980's many HDB flats slope anything that looks and feels like a roof.
This is to prevent birds resting onto the ledge.
With such slopping roof, birds will avoid them like the plaque..

Wild birds + bird flu?

Quote

On 4/17/2013 7:33:39 AM, Anonymous wrote:
Nowadays, there is a major
concern of bird flu and bird
droppings.Since the 1980's
many HDB flats slope anything
that looks and feels like a
roof.This is to prevent birds
resting onto the ledge. With
such slopping roof, birds will
avoid them like the plaque..