There's a company here that sprays on a polyurethane coating for any roof that's guaranteed to last 50 years. It is very expensive though.
One thing to keep in mind is that the cost of housing is skyrocketting. As much as I'd like to build a bullet-proof house, the little amount of remodeling I've done to the trailer I live in hasn't been with the materials I prefer to use since I can't afford them. And if I were to build a house I'm sure the same thing would happen.
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