Metal Roofing vs. Asphalt Shingles in Tennessee's Climate

We install both. Which one we recommend depends on the house, how long you plan to own it, and what your roof does in summer — not on which product carries a better margin.

Lifespan

A quality architectural asphalt roof in our climate generally delivers 25 to 30 years. A properly installed standing-seam metal roof commonly lasts 40 to 50, and often outlives the owner's time in the house. Exposed-fastener metal panels — the corrugated type you see on barns and outbuildings — sit in between, because the neoprene washers on the screws degrade and need periodic re-fastening.

That difference is the core of the financial argument: metal typically costs two to three times as much up front and lasts roughly twice as long, which means the two come out closer than the sticker price suggests — but only if you own the house long enough to collect on it.

Humidity and moss

Our summers are genuinely humid, and that shows up on roofs as algae streaking and, on shaded north slopes, moss. Metal doesn't host either in any meaningful way. Asphalt does, though modern shingles include algae-resistant granules that handle most of it, and the streaking is cosmetic rather than structural. If you have heavy tree cover and a north-facing slope that never dries out, that's a genuine point in metal's favour.

Hail: the honest answer

This is where homeowners are most often misled. Metal is far less likely to fail from hail — it doesn't lose granules or crack — but it can absolutely dent. Large hail on a 26-gauge panel leaves visible dimples that don't leak and don't shorten the roof's life, but do bother people who just spent a premium on their roof. Textured or stone-coated metal hides dents considerably better than smooth standing seam.

Asphalt handles hail differently: it bruises. The mat softens where it was struck and granules come off, and while that doesn't leak immediately, it shortens the roof's life and is generally an insurable loss. If hail resistance is your priority and metal isn't in budget, a Class 4 impact-rated architectural shingle is the practical middle path — and several carriers discount premiums for one.

Heat and energy

In July, a dark asphalt roof surface can reach well over 150°F, and that heat radiates into the attic. Metal reflects considerably more solar radiation, especially in lighter colours or with a reflective coating, and it sheds accumulated heat quickly once the sun moves off it.

The caveat: this only translates into a lower power bill if your attic is properly ventilated and insulated. An unvented attic under a metal roof is still an oven. Fix the ventilation first — it's cheaper than either roof and it extends the life of both.

Noise

The "rain on a tin roof" objection mostly comes from experience with barns, where metal is fastened to open purlins with nothing underneath. A residential metal roof over solid decking, synthetic underlayment and an insulated attic is only marginally louder than shingles in a downpour, and many people like the sound. If you have a finished room directly under the roof deck with minimal insulation, that's worth discussing before you commit.

Appearance and neighbourhood fit

Standing seam suits modern and farmhouse architecture and looks deliberate on it. On a traditional brick colonial in an established Brentwood or Franklin neighbourhood it can read as out of place, and some HOAs restrict it outright. Check your covenants before falling in love with a colour chart. Metal shingle and stone-coated products exist specifically to bridge that gap.

Which we'd recommend

Metal makes sense when:

• You intend to stay in the house 15+ years, or want a roof the next owner never has to think about
• The roof is simple — long uninterrupted runs, few penetrations, minimal valleys
• Heavy tree cover keeps slopes damp, or attic heat is a known problem
• The architecture and the HOA both suit it

Asphalt makes sense when:

• Up-front cost matters, or the work is an insurance replacement where metal means a large out-of-pocket upgrade
• The roof is complex, with many dormers, valleys and penetrations — complexity raises metal's cost sharply
• You may sell within a decade
• You want hail protection without the premium — a Class 4 shingle gets you most of the way

We'll price both for your specific roof so you're comparing real numbers on your own house rather than national averages. Request a free inspection and ask for both options in the quote.