20-30 years or longer.
There's no such thing as a 20-year asphalt shingle. . . life expectancy of these shingles can only be truly rated to three or four years. . . . We can only hope that the 2-year shingle will last five to seven years.. - Laurence Seaton, Bunnell Construction Letters to the Editor, Western Roofing Magazine. The heavier the shingle, the longer the wearing surface lasts. If shingles are dark in color and lightweight(180 lbs) expect a life of 7 to 9 years. For a 400 pound fiberglass shingle, you can expect about 17 years. For weighs somewhere in the middle, expect a life of about 12 to 15 years. Caution: 1  Stay with lighter colors for longer shingle life expectancy. The average lifespan of asphalt shingles ranges from 20 to 40 years depending on the manufacturer, although many warranties only guarantee between 15 and 25 years. Fiberglass shingles are more expensive, but can last more than 50 years. Modern asphalt and fiberglass shingles come with attractive warranties of 25, 30 and even 40 years. However, these warranties are generally just marketing tools that have little bearing on the actual life span of the shingles. Twenty year shingles do not usually last much longer than about fifteen years and may show signs of deterioration between ten and twelve years. Twenty-five year shingles have a useful life of about eighteen to twenty years. Thirty-year shingles have about a twenty-five year life expectancy. Inspect the roof regularly, when it begins to look a little rough it's probably time for a re-roof. If its too high to get on, use a pair of binoculars. Fiberglass shingles generally have a longer life expectancy than do asphalt shingles. Properly installed tiled roofs have a normal useful life of 20-30 years or longer, but individual pieces can become cracked or broken or the nails rust out.
http://vancouverislandsbestroof.com/ashphalt-fiberglass-roof.html http://arizonaroofer.net/fiberglass-shingles/ http://homeguides.sfgate.com/average-life-roofing-94238.html http://vancouverislandsbestroof.com/ashphalt-fiberglass-roof.html http://www.greatinspector.com/frequently-asked-questions/faq-rs/life-expectancy-of-roof-shingles/ http://realty-chek.com/htm/Roofing.htm
fiberglass shingles life expectancy