[LookingForCruiser]

I've read that fiberglass has a lifetime of 40-50 years. After that it has presumably lost a lot of its structural integrity due to flexing.

Now, I've also read (on the sailnet forums) that a lot of people seem to think that the older boats are the way to go (due to thicker fiberglass, non-cored hulls, cost issues, just liking the look of older boats, etc).

At this point, is a late 60's / early 70's fiberglass boat on its last legs, or will they last quite a bit longer?

I'm thinking specifically about an early 70's Iroquois cat - that's in the price range I'm thinking of for a cruising cat, even taking in the cost of a major refit. But if the hull is going to fall apart at some point in the next 10 years it seems foolish to blow a lot of money on a refit.

Also, while I read that fiberglass has a lifetime of 40-50 years, how exactly does it fail? Does the boat just sink one day? Fall apart in bad weather? Just more prone to getting big holes if you bump the dock too hard?