What is the truth about metal roofs?
Short answer. The truth is that metal roofs last much longer than shingles and handle wind and heat well, but they cost considerably more up front, can dent in hail, and are only as good as the installer's trim and fastener work. Many common fears, such as metal attracting lightning or being unbearably loud, are myths when the roof is built over a solid deck.
Myths
- Metal attracts lightning. It does not make a strike more likely, and if lightning does hit, a metal roof will not burn.
- Rain is deafening. Over a solid deck, underlayment and an insulated attic, rain sounds much like it does on shingles. Noise complaints usually involve panels over open purlins.
- Metal makes the house hotter. Light or reflective finishes bounce much of the sun's heat, and metal sheds heat quickly after sunset.
- Metal rusts quickly. Galvalume and quality painted steel resist rust for decades; trouble starts at cut edges, scratches and the wrong fasteners.
Facts that cut the other way
- Cost. Metal usually costs well more than an architectural shingle roof, especially standing seam.
- Hail dents. Large hail can dent panels, and many policies exclude or limit purely cosmetic damage to metal, so read yours before you buy.
- Exposed screws need care. The rubber washers on exposed fastener panels age in the sun, and screws often need tightening or replacing over the roof's life.
- Installer skill. Leaks on metal usually come from trim, flashing and penetrations, not the panels.
Lifespan, honestly
Standing seam commonly lasts 40 to 70 years and exposed fastener panels often 25 to 40 with screw maintenance, compared with about 20 to 30 years for architectural shingles in Georgia. That math only pays off if you stay in the house long enough to collect it. Compare in metal roofing in Georgia and how long a roof lasts in Georgia.