What Is a Metal Roof Coating?
A metal roof coating is a protective liquid layer that seals and waterproofs your metal roof. Unlike paint, which is purely aesthetic, coatings provide waterproofing, UV protection, and structural integrity. They bond to the metal surface, creating a seamless barrier that prevents rust, stops leaks, and extends roof lifespan by 10–20 years beyond the original.
Why metal roofs need coatings:
Metal roofs deteriorate from:
- Salt spray corrosion (critical in Myrtle Beach's coastal climate)
- UV radiation (Myrtle Beach averages 214 sunny days/year)
- Humidity and moisture (coastal South Carolina averages 70% humidity)
- Thermal expansion and contraction (metal expands/contracts with temperature changes)
A quality coating seals fasteners, seams, and the entire roof surface, preventing rust-through and extending your roof's lifespan to 50–75+ years total.
Types of Metal Roof Coatings
Choosing the right coating depends on your priorities: durability, cost, flexibility, or energy efficiency. Here are the four main types.
Silicone Coatings
Silicone is the premium choice for coastal climates like Myrtle Beach.
- Properties: Excellent UV resistance, highly reflective (reduces heat), waterproof, flexible, and long-lasting.
- Durability: 20–25 years (longest-lasting option)
- Cost: Premium pricing (contact for quote)
- Best for: Sunny, coastal climates with high UV exposure and salt spray
Pros:
- Longest lifespan (20–25 years)
- Highest reflectivity = significant energy savings in Myrtle Beach
- Excellent salt spray resistance (critical for coastal areas)
- Can bridge small cracks
- Maintains flexibility in temperature swings
Why it's best for Myrtle Beach: Silicone's superior UV resistance and salt spray protection make it ideal for coastal South Carolina. The high reflectivity reduces AC costs significantly, and the 20–25 year lifespan provides excellent ROI for homeowners.
Polyurethane Coatings
Polyurethane excels in humid environments with extreme weather.
- Properties: Flexible, durable, good adhesion, resistant to foot traffic and movement.
- Durability: 15–20 years
- Cost: Mid-range pricing (contact for quote)
- Best for: Metal roofs in freeze-thaw climates or with significant expansion/contraction
Why it's good for Myrtle Beach: While silicone is superior, polyurethane is an excellent alternative for humid coastal climates. It handles the moisture and humidity well and provides solid 15–20 year protection.
Acrylic & Rubber Coatings
Acrylic is budget-friendly; Rubber is specialized for waterproofing.
- Acrylic: Budget-friendly, 8–12 year lifespan. Not ideal for Myrtle Beach's intense UV/salt spray.
- Rubber: Mid-range pricing, 10–15 year lifespan. Excellent waterproofing and handling of coastal humidity.
Key Benefits of Metal Roof Coatings
Extended Roof Lifespan
Metal roofs naturally last 40–60 years. A quality coating adds 10–25 additional years, extending total roof life to 50–85 years. This delays costly replacement by 15+ years, saving significant money.
Energy Efficiency & Cost Savings
Reflective silicone coatings reduce roof surface temperature by 30–50°F, significantly lowering AC costs in Myrtle Beach. Over a 15–25 year lifespan, this adds up to substantial energy savings.
Waterproofing & Leak Prevention
Coatings seal fasteners, seams, and the entire roof surface, preventing water intrusion and rust-through. This saves thousands in hidden mold, rot, and structural damage repairs.
UV & Weather Protection
Coastal Myrtle Beach faces intense UV (214+ sunny days/year), salt spray, and 70% humidity. Quality coatings protect against all three, preventing rust, corrosion, mold, and structural deterioration.
DIY vs Professional Application
❌ DIY Risks
- Safety hazards (falls from heights)
- Improper surface prep = adhesion failure
- Warranty automatically void
- Weather-dependent (curing issues)
- Poor longevity (5–10 years instead of 15–25)
- Time-intensive (2–5 days of work)
✅ Professional Benefits
- Full workmanship warranty (10–20 years)
- Expert surface preparation
- Problem-solving (leak repair, damage assessment)
- Safety compliance & insurance
- Faster timeline (1–3 days)
- Full coating lifespan achieved (15–25 years)
Cost comparison: DIY may seem cheaper upfront but requires more frequent recoating (5–10 years). Professional application lasts 15–25 years. Professional ROI is clear: invest in quality now, save significantly over time.
Application Process & Best Practices
Pre-Application (1–2 days)
- Inspection: Assess roof condition, identify damage/rust
- Cleaning: Pressure wash (1,500–3,000 PSI); allow 24–48 hours drying
- Repairs: Grind rust spots, seal seams, patch damage
- Priming: Apply primer if required by manufacturer
⚠️ Critical Environmental Conditions
- Temperature: 50–85°F (outside range = curing failure)
- Humidity: <85% (Myrtle Beach often exceeds this)
- Weather: No rain for 48 hours post-application
Post-Application (7–14 days)
- No foot traffic for 7–14 days (allow full cure)
- Don't pressure wash for 6 months
- Schedule annual professional inspection
Choosing the Best Coating for Your Roof
For Myrtle Beach Climate
🥇 Top Choice: Silicone
Superior UV/salt spray resistance. 20–25 year lifespan. Premium pricing. Significant energy savings (typically pays for coating in 5–10 years).
🥈 Alternative: Polyurethane
Excellent humidity handling. 15–20 year lifespan. Mid-range pricing. Best if budget is a consideration.
🥉 Budget: Rubber
Superior waterproofing, handles humid coastal climate. 10–15 year lifespan. Affordable pricing. Best for roofs with existing damage.
Frequently Asked Questions
Q: What's the best coating for a metal roof?
Silicone (20–25 yr lifespan, best UV/salt spray resistance) for Myrtle Beach. Polyurethane (15–20 yrs, excellent humidity handling) as alternative. Acrylic (budget-friendly but only 8–12 yrs) or Rubber (10–15 yrs, superior waterproofing). For coastal properties, silicone or polyurethane provide best long-term value.
Q: How long does a metal roof coating last?
Silicone: 20–25 years | Polyurethane: 15–20 years | Rubber: 10–15 years | Acrylic: 8–12 years. Coastal climates reduce lifespan 2–5 years. Professional application + annual maintenance extends total roof life 10–25 additional years.
Q: How much does it cost to coat a metal roof?
Materials by type: Acrylic (budget-friendly) | Rubber (mid-range) | Polyurethane (mid-range) | Silicone (premium). Costs vary based on roof size, condition, and accessibility. Contact us for a free estimate tailored to your specific roof.
Q: Can I apply coating myself?
No—too risky. DIY risks: falls (safety), improper prep (adhesion failure), voided warranty, poor curing conditions, short lifespan. Professional benefits: full warranty, expert prep, problem-solving, safety, faster timeline, 15–25 year lifespan.
Q: Silicone vs Polyurethane—which is better?
Silicone: 20–25 yrs, excellent UV/salt spray, high reflectivity with significant energy savings, premium pricing. Polyurethane: 15–20 yrs, superior flexibility, good humidity handling, mid-range pricing. For Myrtle Beach: Silicone edges out for coastal protection.
Q: How often do metal roofs need recoating?
Silicone: rarely (20–25 yrs). Polyurethane: 15–20 yrs. Rubber: 10–15 yrs (refresh at 10). Acrylic: 8–12 yrs (refresh at 6). Minor repairs can delay full recoating 5+ years, saving significant money.
Q: Do coatings save on energy costs?
Yes. Reflective silicone reduces roof temp 30–50°F, lowering AC 10–20%. Myrtle Beach homeowners see significant annual savings that add up over 15–25 years. The coating typically pays for itself in 5–10 years through energy savings alone.
Q: Is coating the same as paint?
No. Coatings: thick (15–30+ mils), waterproofing + UV, 10–25 yrs. Paint: thin (1–3 mils), aesthetic only, 3–7 yrs. For metal roofs, coatings are correct choice for long-term protection.
Q: How do you prepare a roof for coating?
Critical steps: (1) Inspect (2) Pressure wash to clean all debris (3) Repair rust/damage (4) Apply primer if required (5) Verify clean/dry. Allow 24–48 hrs between steps. Poor prep causes adhesion failure—this is where pro expertise saves money.
Q: Is it worth coating a metal roof?
Yes—excellent ROI. Coating is significantly more affordable than full replacement and lasts 15–25 years. Delays replacement 15+ years. Smart investment for roofs 5+ years old in Myrtle Beach. Contact us for a free assessment.
Get Your Free Inspection Today
Not sure if your metal roof needs coating? WeatherShield offers free professional inspections. Our Myrtle Beach experts can assess your roof's condition and recommend the best solution.
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