cost of asphalt roofing
1 If removing and disposing of the existing roofing material isn't included in an estimate, this can add another $3-$5 a square foot or $510-$1,100 for a basic ranch-style home -- and costs go higher depending on location and the difficulty of the removal project. According to RoofHelp.com, the average lifespan for 20-year asphalt shingles is about 14 years in Phoenix, Arizona; 19.5 years in Minneapolis, Minnesota; and 20.8 years in Reading, Pennsylvania.