Shingling Hips And Valleys; Flashing; Saddle Or Comb Boards. Hip and valley shingles are usually sawed to shape before being taken to the roof, the face cut being the same as that used across the face of the roof boards and plancher members intersecting about a corner of a hipped roof where plancher lies in the plane of the roof. The cut across the edge of such shingles is made square to the face.
Of the many ways of protecting the intersection of hip shingles when in place upon a roof, the simplest is that of employing tin shingles. Such shingles should be of sufficient length to allow the corners to be turned under as shown in Fig. 105, and still extend far enough under the next course of shingles to permit the nails holding the tins to be covered. It is not good practice to nail thru these tins after the roof has been covered, that is, to place these tins after the roof has been shingled because the action of the weather "lifts" the nails when exposed thus.
Fig. 105. Shingle Tins.
Fig. 106. Valley.
Valleys are covered with a strip of metal to a width of 20 inches. Upon steep roofs and short valleys this width may be reduced to
16 inches. Space must be left between the edges of valley shingles as shown in Figs. 106 and 107. The amount will depend upon the length of the valley and the steepness of the roof. For a pitch with a length of twelve to fourteen feet of valley, the space at the top of the valley may well be 1 inch to each side of the valley center line, widening gradually toward the lower end to 2½ inches to each side. Chalk lines snapped upon the tin or other metal forming the valley indicate the location of shingle edges. Nails in valley shingles should be kept well back from the valley edge of the shingles.
Fig. 107. Shingling Valley.
Flashing consists in placing tin shingles or other material about the members making up a joint so that the joint shall "turn water." Counterflashing consists in placing a double layer of tins in such a way as to doubly insure turning water from a joint.
Fig. 108 is an illustration of flashing where shingles meet lap siding. Shingle tins are forced under the siding on one side and either under or over the shingles, several inches of lap being allowed all about.
Fig. 109 illustrates a counterflashed chimney. A layer of tins is placed as in flashing against siding except their top edges are not inserted. Over these tins a second layer is placed as shown, the top edges being inserted ¾ " between the layers of brick, the mortar being raked out so that this can be done. These turned edges are held in place by theinsertion of a wedging nail or tack, after which the cracks are filled with cement, or better, an elastic roofing composition.
Tins should be carried high enough to prevent drifted snow from entering; 2½ or 3 inches at the narrowest place.'
Fig. 108. Flashing.
Fig. 109. Flashed and Counter-flashed.
Saddle or comb boards are of various forms. They are used to give the ridge a finished appearance and to turn any water which might happen to strike thereon; also to hold the last course of shingles in place. A simple form is obtained by creasing to the appropriate angle a strip of tin eight inches in width. Place this on the ridge and nail its edges at intervals of 3 or 4 inches. Where boards are used, one board should overlap the other and extend a half inch beyond to turn water from the joint so made. Galvanized ridge rolls may be purchased in stock styles.