Roof materials - Shingles and Shakes Resource
Asphalt Shingle Roof
Dimensional Shingle Roof
Composition shingles are used on the majority of homes in the United States. These shingles are made of a base (organic or fiberglass) that is saturated with asphalt and coated with minerals on one side to resist weathering. The fiberglass shingles are more flexible and stronger than organic shingles. Shingles come in a wide variety of colors. Composition roofs can be overlaid with a new roof if the initial roof is a single layer and in good condition. The life expectancy of composition shingles depends on the rating (e.g., quality) and ranges from 20 to 30 years. Most manufacturers will cover a composition roof under warranty, but only if it has been installed by a certified roofer as the most common problems and maintenance issues occur when the installation did not include adequate ventilation and or flashing.
Dimensional shingles are very similar to composition shingles, but are thicker, and can be used to create a more custom appearance. Depending on the rating, dimensional shingles also have a much better lifespan, with an expectancy of up to 40 years. The issues and concerns with a dimensional roof are the same as those associated with composition shingles, moss buildup, quality, and adequate venting/flashing.