That roof will last a lifetime Gene, did the same thing here. Screwed down heavy gauge metal. Being a light color it reflects the sun instead of absorbing the sun's heat from dark shingles. Roughly 30 % more efficient in the cooling capacity in the house. Cost is higher initially of course, but pays for itself very quickly. Plus, it's a classic look in my opinion. My son wanted the same on a house he had built in Houston, but apparently the subdivisions in Houston won't allow that for some reason.