Whenever I sit on the roof I see many kinds of birds. One of the reasons they come is because of the water on the roof. It is very hot, lack of clean water tells why birds are coming to the roof. I have blocked the drains on the roof with polythene so that the water does not pass through the drains quickly but stays on the roof for the birds to drink. Most of the pigeons and sparrows come here to drink water. You can do it on your roof too for the sake of bird's life in this hot condition.