Slopes in four directions, has a gable, or deck above. Contrary to the name, a flat roof is sloped, but only enough for drainage, usually only on-eighth to two inches for every foot of horizontal 6. Is a roof that slopes in only one direction. D. Roof framing 1. rafters. Rafters are the upper chord of a roof truss.
Common rafters are rafters of small size.
In a common rafter roof all the rafters are of the same size. Principal or common. Web members of a rafter truss that are in tension. E. Roof sheathing and cladding 1. Sheathing is the timber that provides the continuous structure upon which the covering is placed.