Roof Flashing is used to weather proof the penetration of chimney pip through the roof. A storm collar is required (not included) . Select the proper roof flashing based on the pitch of the roof. For example, a 6/12 pitch has a vertical rise of 6"" over a horizontal distance of 12"". DuraTech is a double-wall, all-fuel chimney system for use with wood stoves, fireplaces, furnaces, boilers, ranges, water heaters, or other appliances fueled by wood, oil, coal, or gas, and zero-clearance fireplaces that are factory-built.See all 8"" DuraTech Chimney Components.