Over the years two strip type asphalt shingles have dominated the market: the 3-Tab asphalt shingle and the Laminated asphalt shingle, sometimes called an Architectural asphalt shingle. There are several manufacturers of asphalt shingles, however there is not much difference in the makeup and to some extent the design from one manufacturer to another.
Asphalt shingles are generally made of a spun fiberglass mat but can be made of an organic or polyester type mat. Most are saturated with asphalt but can be saturated with modified bitumen. All are coated with ceramic granules. There are several manufacturers of asphalt shingles.
The 3-Tab asphalt shingle is generally 36" long by 12" wide with two cutouts in the lower portion of the shingle making it appear, once installed, as individual shingles. This type of strip shingle is the least expensive roofing material.
The Laminated asphalt shingle is made of two pieces laminated together. One piece is about 36" long by about 6". Another piece is laminated over it commonly called the dragon's tooth piece because it resembles squared off teeth. This type is more expensive and can be very expensive if marketed by the manufacturer as a 50 year or lifetime roof.
There are a few other styles of strip shingles now available which present a different appearance, sometimes called Architectural asphalt shingles. Some are a one-piece dragons tooth, others have a few layers of differently cut asphalt shingles all laminated together. These are the most expensive types of asphalt shingles.
The manufacturers market their shingles as 20, 25, 30, 35, 40, and even 50 year or Lifetime asphalt shingles as a way of differentiating several 3-Tab or Laminated and Architectural shingles they sell. They make it sound as if they will last that long. There may be differences in the amount of asphalt they use or they may have a thicker mat and look or they might be granulated on both sides and have more self-sealing asphalt for better wind resistance. But in the end, an asphalt shingle still is an asphalt shingle. No matter what little changes they make, they all look similar in that they all are covered with granules and their performance is similar.
When specifying Asphalt Shingles, make sure to state the Manufacturer, the number of years warranted, name of the shingle, color, and type. Example: Acme, 30 year, Wind Star, Sand Dune, 3-Tab Asphalt Shingle. (Made up shingle)
The life expectancy of any asphalt shingle varies in different climates. Around here in Colorado the life expectancy is at the most 20 years for 3-Tab shingles and maybe 25 years for Laminated shingles no matter what their marketing/warranty says. This is because the sun's intense ultraviolet rays bleach out the asphalt very rapidly compared to other parts of the country. So basically, a 30 year asphalt shingle will last about the same amount of time as a 50 year or Lifetime asphalt shingle roof. After all, they all are made of the same materials.