Climate Talk

White roofs in Egypt? Why don't we paint all the roofs!

I read that white or reflective roofs can make the inside of a building cooler in summer. In Egypt we have so many flat concrete roofs, many are just grey or have satellite dishes and water tanks!

If all roofs in Cairo were white, would the city be less hot? Is it expensive? I want to try on my family's building but my uncle says it's a waste of money. Who is right?