Asphalt shingles are currently the most popular type of residential roof material for a variety of reasons. Things that determine cost are geographical location, slope of the roof, height of the building, ease of access to the premises, complexity of the project, the particular type of shingle and numerous other factors. They come in a variety of colors and styles, are fairly durable (some have been tested and have achieved a class IV hail rating - the highest available!), and can be easily repaired and maintained.