Book 13, Question 42
Why Are Roofs in Hot Places Often Painted White?
Roofs in hot places are painted white because a white roof reflects more sunlight and stays cooler.
White roofs reflect most of the Sun's light instead of soaking it up. Dark roofs absorb sunlight as heat. So white roofs keep buildings cooler inside!
Watch the videoWatch on YouTubeSee the series on Amazon
Quick answers
How much cooler can a white roof be?
A clean white roof that reflects 80 percent of sunlight can stay about 31 degrees Celsius cooler on a summer afternoon.
Sources: BBC, National Geographic, NASA, National Geographic
More fun facts
- Painting a roof white makes it reflect more sunlight and stay cooler.
- A clean white roof that reflects 80 percent of sunlight can stay about 31 degrees Celsius cooler on a summer afternoon.
- Researchers found that painting black roofs white can lower city temperatures a lot.
- One estimate says painting flat roofs white worldwide would cut as much carbon as taking all cars off the road for 11 years.
- Scientists have also made a glass based paint that helps keep metal roofs cool.
Sources: BBC, National Geographic, NASA, National Geographic
Questions kids ask
Why do dark roofs get so hot?
They absorb more sunlight instead of reflecting it.