As with most home improvement choices, there is a direct relationship between quality and expense, and in the case of roofing, quality usually translates as longevity. With a roof, it rarely makes sense to shop by choosing a roofing material based sheerly on price, when spending a little more may give you a roof that lasts for as long as you own the house. A cheap roof is no bargain if it needs to be replaced every 8 years.