Increasing the roof pitch of a home can provide better drainage, and might be the best solution for people who have flat or very low pitch roofs. Raising the roof pitch does mean building a new roof, although tearing the old one off is sometimes optional. Leaving the old roof behind offers more roof protection, but it also increases the weight being supported by the walls dramatically. For the sake of increased home safety, removing the old roof is worth serious consideration.
Set braces on either side of the roof peak which extends up the distance you are raising your roof. Use a plumb-bob to keep the braces perfectly perpendicular. The braces are an easy way to get the correct angle to cut the top ends of your rafters, too. Simply use the edge of one brace to mark a piece of scrap lumber, cut the angle, and use it for a template in future cuts.
Quick Roofing Tips
Be sure that you use sufficient "V" bracing to support the new roof. Rafters should be placed on either 16 or 24-inch centers, and are usually cut from 2x6 lumber. Always keep the crown side of lumber up, or away from the direction of the load.