How long a roof lasts depends partly on its shape, its pitch, the weather to which it is exposed, the insulation below it and the maintenance it receives. The most important factor is what the roof surface is made of.
Most home owners replace their roofs before the full life – as projected at installation – has expired. Sometimes, a roof is replaced because a home renovation plan required it, but often it is done because homeowners become frustrated with persistent water leaks. (Those, by the way, can be successfully detected with water leak testing and eliminated by a waterproofing company or a roofing contractor). Leaks are caused by poor maintenance, and timely repair can greatly extend a roof’s life.
Small repairs to roof flashing, valleys, and worn areas can postpone the need to replace a roof for years. Exceptionally long-lasting roof materials – such as slate, clay tile, and metal – have lasted 100 years or more with yearly preventive maintenance and repairs. As a rule of thumb, you can afford to spend $40 to $80 in repairs for every year of extended roof life the repairs will permit; and a good roofer can estimate how long the roof repairs will last.
The key to cost effective roof repairs is periodic roof inspection to catch problems early, particularly when the roof covering is 15 to 20 years old or the age of the roof is uncertain. Become an expert on your roof, or ask a roofing specialist have a professional look at it occasionally.
But even with the best of care, the roof material must be replaced eventually. Asphalt shingles are a common, sinsible choice.
Remember, no matter what the new roof is made of, it should be leak-free; last at least 20 years; require very little maintenance; and stand up to abuse from snow, ice, and wind.