Why do different shingles carry different warranties?
In today’s market, there are many types and styles of shingles available. The various types of shingles come with warranties representative of the life expectancy of each type. Generally speaking, the heavier the shingle, the longer the warranty. Therefore a 20 year shingle is lighter in weight than a 25 year shingle. All other things being equal, the weight difference comes from the amount of waterproofing material used during the manufacturing process.
