5. Whether or not you should expect wood rot depends upon the age of your house, and whether it was shingled properly. Most wood rot is contained to the bottom 12 inches of the roof. It is hard to determine the extent of rot without removing the shingles. Your contractor should make you aware, before the job is started, if he expects to find rot, and how much the per linear foot price is to replace it.

Here is an example of some rotten boards removed while roofing a house. This was all at the bottom edge of the roof, and might have been avoided if the roof had drip edge.