Carpentry & Building ConstructionChapter 18:
Hip, Valley, & Jack RaftersChapter SummariesSection 18.1 Hip Rafters
The length of a hip rafter is calculated on the basis of the unit run and unit rise and/or the total run and total rise. Any of the methods previously described for determining the length of a common rafter may be used. However, some of the basic data for hip and valley rafters is different. Section 18.2 Valley Rafters
The span of an addition roof may be equal or unequal to that of the main roof. Dormers are framed either with or without side walls. Those with side walls are called doghouse dormers. Section 18.3 Jack Rafters
Jack rafters are shortened common rafters framed to a hip rafter, valley rafter, or both. The best way to figure the total lengths of valley jacks and cripple jacks is to lay out a framing plan. A hip jack rafter extents from a hip rafter to a plate. Hip jacks always have the same spacing as common rafters.  | 
