Metal roofs are proven to last two to three times longer than asphalt, with 50 to 60 years lifespan for high-end metal roofs such as field-locked standing seam and aluminum shingles.
A roof made of zinc or copper can last well over 100 years.
Metal roofing is the perfect choice for heavily wooded areas; shingles such as asphalt and wood (cedar shingles and shakes) are prone to moss and fungal buildup which shortens their lifespan. Metal roofing is 100% unaffected by the growth of mildew, fungus, and moss. In addition, rodents like racoons who can get onto your roof from the trees, won’t be able to get through a properly installed metal roof and into your attic space. Shingles, on the other hand, can be broken away by pests and wild animals thus destroying your plywood decking/ attic space and at that point are even able to get inside your home!
Fire resistance is another perk of having a metal roof since metal is noncombustible; many are led to believe that they are lightning rods. The material covering your roof, however, isn’t what determines whether it will be struck. That would be more determinant on the placement and size of the building. Metal roofs can be struck by lightning BUT when it happens its far less dangerous than a strike on a shingle roof. The outcome of the strike depends on the structure of the building since electricity passes more easily through a good conductor (copper, steel) than it would through a poor conductor (wood, concrete). A poor conductor (shingles) has more electrical resistance, which converts the lightning’s energy into heat, in turn, resulting in fire or even explosions.
SO what happens when your metal roof is struck by lightning? The electrical charge is dispersed throughout the entire roof rather than on an asphalt roof where lightning would hit and stay in that one spot, in-turn, causing a fire. Remember: Metal is non-combustible; shingles are combustible.