When people compare metal roofs, they often mix up the panel style (standing seam vs. corrugated) with the metal's coating. Galvalume, galvanized, and painted aren't roof "types" — they're the finish on the steel, and that finish is what determines how well your roof resists rust and how it looks. Here's the difference.
Quick comparison
| Coating | What it is | Corrosion resistance | Look | Best for |
|---|---|---|---|---|
| Galvalume | Aluminum-zinc alloy coating on steel | Excellent | Bare silver/spangled | Best all-around value |
| Galvanized | Zinc-only coating on steel | Good | Bare silver, duller over time | Budget / traditional |
| Painted (Kynar/PVDF) | Color paint over Galvalume | Excellent + color protection | Any color, matte or gloss | Homes wanting a specific color |
Galvanized
The original coated steel — zinc bonded to steel. The zinc sacrifices itself to protect the steel from rust. It works, but in most climates Galvalume outlasts it, so galvanized is less common for new residential roofs today.
Galvalume
Galvalume coats the steel with an aluminum-zinc alloy (roughly 55% aluminum, 45% zinc). You get aluminum's excellent corrosion resistance plus zinc's sacrificial protection — the best of both. It typically outlasts plain galvanized and is the industry standard base for most metal roofs. Learn more in our what is Galvalume guide.
Painted (Kynar / PVDF)
Most colored metal roofs are painted Galvalume — a premium PVDF (Kynar 500) coating over a Galvalume base. You get the corrosion resistance of Galvalume plus fade-resistant color in dozens of options. If you want black, charcoal, or any specific color, this is what you're getting.
Which is best for a Tennessee roof?
For Middle Tennessee's heat and humidity, we recommend Galvalume or painted Galvalume. Bare Galvalume gives you maximum durability at the best value; painted Galvalume adds color and fade resistance. We install both standing seam and screw-down panels in Galvalume and painted finishes — ask us which fits your home and budget.