Concave Juncture

Metal flashing for the concave juncture (Figure 11) are similar to those for the convex type. They should be installed to cover the top of the roof slope and the bottom 4" (101.6 mm) of the wall before the final course of shingles or shakes is installed. The final roof course should be installed so that the tips fit as snugly as possible against the wall at the juncture. A double starter course should be applied at the start of the wall surface and the remaining wall courses applied in the recommended manner.

Apex Juncture

On this roof juncture (Figure 12) metal flashing should cover the top 8" (203.2 mm) of the roof and the top 4" (101.6 mm) of the wall. It should be installed before the final course of shingles or shakes is applied to the wall. The recommended sequence of application is to apply shingles or shakes first to the wall then to the roof. The overhanging roof material is then trimed flush with the wall. Finally, specially prepared ridge units are applied over the wall-roof juncture so that in each matching pair the roof piece overlaps the wall piece each time.

Swept of Bell Eave

When shingles or shakes are to be applied to a swept or bell eave where the curvature is excessive, it may be necessary to soak them for a period (usually overnight) or steam them prior to installation. (Figure 12, page 12). A double starter course is employed in the usual manner. Exposure is determined by the scope of the roof and the type of shingle or shake selected.