Slate roof is stunning, enduring, waterproof, and fire-resistant but they are heavy as well. A usually installed slate roof would weigh at least 640 lbs. /sq. while using an authentic “lightweight” slate. But if the roof weighs lesser, then slates are perhaps very thin to be able to possess a practical life span. The 12″ × 10″ slate tile is simple to hold, because only the ridge, hip, valley tiles are fixed, installation time will decrease significantly. A usually installed standard weight slate roof normally weighs 900 lb. /sq.