How Long Should a Roof Last?
The average life span of a typical roof varies dramatically and may range from as few as ten years to as many eighty or even one hundred years or more. A number of factors can affect the life expectancy of a roof including material used and its quality, pitch of the roof, climate, direction the roof faces and maintenance.
The most common material for roofing is asphalt shingles, which have an average life expectancy of 15-30 years. Wood roofing typically has a life span of 10 to 40 years, depending on quality of the wood and whether the wood is hand or machine sawn. Slate, metal, and clay or cement tile roofs have a much longer life expectancy.
High quality slate, clay or cement tile roofs may last 50-80 years, and metal may last as long as 150 years. Ensuring the use of high quality materials that have been stored and installed properly will maximize that life span of any type of roof.
Exposure to weather, especially sunlight, can significantly shorten a roof’s life expectancy. In warm climates, if the house is not adequately ventilated, the surface temperature of the roof will remain high thus shortening its life. In hotter climates, roof life span is generally shorter.
Heavily shaded areas, especially with a low slope, may be prone to growth of moss and mildew, which can damage the roof. Similar growth of moss and mildew can occur in especially damp climates as well. In areas that receive significant snow and ice, it is important to ensure that ice dams do not form and force moisture underneath the roof, as this can cause damage and leaking.