What is a splice?
Large rolls of organic felt or glass mat are used in the shingle manufacturing process, and a splice is a glued or taped lap of the end of one roll to the beginning of the succeeding roll. Rolls of dry felt or glass mat must be spliced together to maintain continuous shingle production. Each splice is marked for rejection before the shingles are packaged. Occasionally, an error or oversight occurs where that splice gets packaged along with the shingles. Shingles containing a splice will delaminate on the roof within a few months, and should be replaced.
