And the Fire Problem

Ask your local firefighters about shake roofs and you will get an ear full. They will tell you that wet shake roofs are very slippery. In the summer, a dry shake roof doesn't just burn, it can explode. And a burning shake roof can through off embers and help spread the fire.

In some parts of the country wood roofs may only be used if they are treated with a fire retardant (not to be confused with shakes treated against rot). As we build more houses in forested areas, roofs with good fire resistance make more and more sense. I picked a metal roof for my cabin in the forest. Concrete and concrete composite products are another good choice.

Article: 
Cedar Roofs