Cedar, as a roofing material, has a long tradition of quality, used for hundreds of years. Cedar makes for the best natural roofing for two reasons: (1) The heartwood has accumulated natural oils which reduce wood rot and insect damage. (2) It also tends to be straight grained, which means that it can be manufactured into shakes and shingles that will remain flat and true. Cedar shake roofs have been known to last over 70 years. Keeping the Cedar shake looking new will require that you use a quality sealer on a regular basis (once a year). Left untreated, the shakes will weather to a rich gray, giving the roof a more rustic look.