Hip and valley construction,
including the proper sizing of
hip and valley rafters, is an
aspect of wood frame construction
that is not generally well understood
and is often poorly executed. There
are two important structural aspects of
hip and valley rafters: sizing the member
and providing support at the ends.
In plan view, hip and valley framing
are similar: In either case, a main structural
member — the hip rafter or valley
rafter — runs diagonally between the
high (ridge) corner and the low (eaves)
corner of an area of intersection of two
sloping roofs. At outside corners, this is
a hip rafter; at inside corners, it's a valley
rafter. Because their geometry is similar,
the same