The 100-year plus materials are lead, tile, slate, and metal. When lead finally corrodes after a century or so, it needs to be completely replaced. Tile and slate are heavy, expensive, and sometimes breakable, but they are fireproof and beautiful, and they will last the life of most buildings (often much longer, since they can be recycled). New concrete tiles are not as attractive as traditional clay tiles- a 12,000 year-old-technology- but they cost less. Slates are soulful. However, they don't hold up in sunny climates quite as well as tile (ultraviolet rots them), they need steeper pitches to reduce moisture damage, and they require stainless steel or copper nails if you want the fasteners to last as long as the slates.
Excerpt: pp 177. How Buildings Learn. Stewart Brand, 1995.
