Steel vs. Aluminum Roofing: Which Metal Is Best for Your WNC Home?

You’ve decided on metal roofing. Now you face another choice: steel or aluminum? Both are proven materials that protect homes for decades. Both work well in Western North Carolina. But they’re not identical, and the right choice depends on your specific situation.

Here’s a straightforward comparison to help you decide.

The Fundamental Difference

Steel

Steel is iron alloyed with carbon and other elements for strength. Roofing steel receives protective coatings to prevent rust:

  • Galvanized: Zinc coating
  • Galvalume: Aluminum-zinc alloy coating (most common for quality roofing)
  • Paint: Applied over galvanized or galvalume base

Steel is heavier, stronger, and less expensive than aluminum. The vast majority of residential metal roofing in WNC is steel.

Aluminum

Aluminum is a naturally corrosion-resistant metal. It doesn’t rust because it forms a protective oxide layer when exposed to air. Roofing aluminum is typically:

  • Mill finish: Natural aluminum appearance
  • Painted: Color-coated for appearance and additional protection

Aluminum is lighter, naturally corrosion-resistant, and more expensive than steel.

Quick Comparison

Factor Steel Aluminum
Cost Lower 30-50% higher
Weight Heavier (1-1.5 lbs/sq ft) Lighter (0.5-0.7 lbs/sq ft)
Strength Higher Lower
Dent Resistance Better Softer, dents more easily
Corrosion Resistance Good with coatings Excellent naturally
Coastal/Salt Performance Fair (requires quality coating) Excellent
Recyclability 100% 100%
Availability Very wide Somewhat limited
Lifespan 40-60 years 50-70+ years

When Steel Makes Sense

For most Western NC residential applications, steel is the practical choice.

Cost Advantage

Steel costs 30-50% less than aluminum for equivalent products. For a typical 2,000 square foot roof:

Steel standing seam: $18,000 – $32,000 Aluminum standing seam: $24,000 – $42,000

That’s a significant difference. Unless you have specific reasons to need aluminum, steel delivers better value.

Strength and Durability

Steel is stronger pound-for-pound than aluminum. This means:

  • Better resistance to denting from hail or falling debris
  • Less oil-canning (waviness in flat panel areas)
  • Greater resistance to damage during installation
  • Better performance under foot traffic

In our mountain environment with occasional hail, falling branches, and steep roofs that may need access, steel’s strength provides practical benefits.

Availability

Steel roofing products are widely available in many profiles, gauges, and colors. Aluminum options are more limited, and some profiles simply aren’t made in aluminum.

This affects both product selection and lead times. If you want specific colors or styles, steel likely offers more choices with faster availability.

Quality Coatings Perform Well

Modern Galvalume coatings (aluminum-zinc alloy) provide excellent corrosion resistance for steel roofing. Quality painted finishes (Kynar 500, Hylar 5000) add another protective layer.

Properly coated steel performs well for 40-60 years in WNC’s climate. The coating technology has advanced significantly over recent decades.

Bottom Line for Steel

Steel is the standard choice for WNC residential metal roofing. It’s more affordable, widely available, and performs excellently in our climate. Most of the metal roofs we install are steel.

When Aluminum Makes Sense

Aluminum costs more, so you should have specific reasons to choose it.

Coastal or Salt Exposure

If your property has unusual salt exposure, aluminum’s natural corrosion resistance provides real value. This might apply if:

  • You’re in a coastal-influenced area (rare in WNC but possible in eastern foothills)
  • Your property is near roads that receive heavy winter salt treatment
  • Industrial emissions in your area are corrosive
  • You have specific air quality concerns

For properties without these factors, Galvalume steel handles WNC conditions fine.

Extreme Longevity Priority

Aluminum roofing can last 50-70+ years, potentially outlasting steel by a decade or more. If absolute maximum lifespan is your priority and budget allows, aluminum delivers.

However, quality steel easily lasts 40-60 years. The practical difference may be whether your roof outlives you by 10 years or 20 years.

Lightweight Requirements

Aluminum weighs roughly half what steel weighs:

  • Steel standing seam: 1.0-1.5 lbs/sq ft
  • Aluminum standing seam: 0.5-0.7 lbs/sq ft

This matters when:

  • Your roof structure has limited load capacity
  • You’re installing over existing roofing (roof-over application)
  • The building is a mobile or modular structure
  • Structural weight is a design constraint

For typical WNC homes with standard framing, weight isn’t usually a decisive factor.

Specific Applications

Aluminum works particularly well for:

  • Pool houses and structures near chlorinated water
  • Boat houses and structures over water
  • Buildings in unusually humid microclimates
  • Structures where maximum corrosion resistance justifies cost

Copper Alternative

Some homeowners consider aluminum as a more affordable alternative to copper when they want a non-steel option. Aluminum offers similar corrosion resistance at lower cost than copper, though without copper’s distinctive appearance.

Performance in WNC Mountain Climate

Rain and Humidity

Both materials handle WNC’s heavy rainfall (47+ inches annually) well. Neither rusts or deteriorates from normal rain exposure.

Steel with quality coatings sheds water effectively. Aluminum’s natural oxide layer protects it continuously.

Advantage: Tie

Temperature Extremes

Both expand and contract with temperature changes. Proper installation with floating clip attachment accommodates this movement for either material.

Aluminum expands more than steel (about twice the coefficient of thermal expansion). This requires careful attention to installation details but doesn’t create problems when done properly.

Advantage: Slight edge to steel (less movement to accommodate)

Snow and Ice

Both shed snow well. Weight isn’t a factor for snow load, the roof structure handles the load regardless of roofing material weight.

Advantage: Tie

Wind

Steel’s greater rigidity may provide slight advantage in extreme wind, but both materials handle WNC’s wind conditions well when properly installed.

Advantage: Slight edge to steel

Hail

Steel resists denting better than aluminum. If a large hailstone hits your roof, steel is more likely to survive unmarked. Aluminum dents more easily.

Neither material typically fails from hail (it would dent, not puncture), but steel’s appearance holds up better.

Advantage: Steel

UV and Sun

Both materials resist UV degradation well. Paint finishes protect both. The underlying metal isn’t damaged by sun exposure.

Advantage: Tie

Overall WNC Performance

Steel with quality Galvalume coating and premium paint performs excellently in WNC conditions. Aluminum would also perform excellently but costs significantly more without providing meaningful advantage for typical mountain properties.

Dent Resistance and Appearance

This deserves separate attention because it’s a meaningful difference.

Steel Dent Resistance

Steel is a harder material. It takes more force to dent. When impacted:

  • Minor impacts leave no mark
  • Moderate impacts may leave small dent
  • Severe impacts dent but rarely puncture

If a branch falls on a steel roof, you may never know it happened.

Aluminum Dent Concerns

Aluminum is softer. The same impact that leaves steel unmarked may dent aluminum noticeably.

For roofs with:

  • Overhanging trees dropping debris
  • Higher hail probability
  • Frequent foot traffic for maintenance

Steel’s dent resistance provides practical value.

Cosmetic vs. Functional

Important note: dents in either material are cosmetic issues. They don’t affect waterproofing or function. A dented metal roof still protects your home perfectly.

But if appearance matters to you, steel’s greater dent resistance keeps it looking better longer.

Making Your Decision

Choose Steel If:

✓ You want the best value

✓ Your property doesn’t have unusual corrosion exposure

✓ Trees or debris might impact your roof

✓ You want maximum product selection

✓ Standard 40-60 year lifespan meets your needs

✓ You have no specific reason to need aluminum

This describes most WNC homeowners.

Choose Aluminum If:

✓ You have specific corrosion concerns (salt, chemicals, unusual exposure)

✓ Absolute maximum lifespan (70+ years) is worth the premium

✓ Weight is a structural concern

✓ The application specifically suits aluminum (pool house, boat house, etc.)

✓ Budget comfortably accommodates the premium

Don’t Choose Based On:

  • Assumptions that aluminum is “better” (depends on application)
  • Fear of steel rusting (modern coatings prevent this)
  • General preference for aluminum without specific reasons

What We Typically Install

At Secure Roofing, the vast majority of our residential metal roofing installations are steel with Galvalume coating and quality paint finishes. This represents the best value for typical WNC homes.

We do install aluminum when homeowners have specific reasons requiring it. We’re happy to discuss whether aluminum makes sense for your situation.

Get Our Recommendation

During your free consultation, we’ll assess your specific circumstances and recommend steel or aluminum based on your actual needs, not assumptions.

Call 828-888-ROOF to schedule your consultation.

Related Articles:

Internal Links to Include:

  • Link to pillar: /services/metal-roofing/metal-vs-shingles/
  • Link to metal roofing: /services/metal-roofing/
  • Link to cost guide: /services/metal-roofing/metal-roofing-cost-western-nc/
  • Link to contact: /contact/