1 Literacy rate, adult female (% of females ages 15 and above) 2  Literacy rate, adult male (% of males ages 15 and above) 3  Literacy rate, youth female (% of females ages 15-24)  Literacy rate, youth male (% of males ages 15-24)
Asphalt shingles- 30 yrs. (only about 15 yrs. of life, though). Tin- 50-100 yrs. You do the math. Tin is way more expensive, but usually works out to save you over the life of the roof (longer than yours). For Canadian weather, I'd strongly recommend the tin as it sheds snow/rain better. Oh, I'm thinking NW Canada, not sure where you live, but still, tin is the better material all the way around.
You are right on both counts DAO1, OSB is cheaper, but not as moisture stable as plywood. Looks like they are using maybe 30 to 40% OSB, strictly as a cost savings. If they were building top quality, they would be using Advent-Tec T&G roof sheathing, which is about twice the cost of OSB and 25% more than good CDX.lywood grasps the nails holding flashing, the finished roofing like asphalt shingles, or the like, better, especially long-term, than OSB which tends to soften more quickly with moisture cycles over the years.