Determining the annual cost of a roof may help provide the best roofing value. The annual cost is figured by using the total of the roof, this includes the supplies and installation expenses. The total cost is then divided by the number of years the roof should last. This technique may prove useful in evaluating roofing bids. For example, if you receive a bid for five thousand dollars and the roof should last 20 years. Your annual cost of the roof would be 250 dollars. This technique can help you evaluate the roof's cost over its lifetime to determine if this is realistic expense to protect your investment. Depending on what caused the need for the new roof, your homeowners insurance may cover a portion of the roofing expenses. Contact a roofing specialist or an insurance agent for more information on figuring the annual cost of your roof.