Being a contractor I can say your insurance company will not pay unless there is damage other than age. That said if you do have damage they will prorate it by age and condition. A lot will depend on your agent too. All above responces are right on. mine are 25 year and been up there 15 and need to replace probably next year or so. Venelation is probably the most important next moss will destroy them by holding moister on and under them. You can avoid the moss with galvinized strips avaliable at your roofing store. There is a formula for how much venting is nessary for how much roof by sq. ft. Now lets get back on the ground and work on some cars