David Karimi
Metal Roofing Specialist18+ years leading WeatherShield's metal roofing division. Personally supervised 500+ metal roof cleanings and restorations across coastal South Carolina.
In This Guide
Key Takeaways
Clean 2-3x Per Year
Coastal roofs need more frequent cleaning than inland
Never Use Chlorine Bleach
Damages coatings and voids warranties
Max 1,200-1,500 PSI
Higher pressure dents panels and strips coatings
DIY: $75-$200
Pro: $375-$750 for 1,500 sq ft roof
Extends Life 5-10 Years
Regular cleaning in coastal environments
Best Schedule
Spring • August • October
Why Should You Clean Your Metal Roof?
Metal roofs are marketed as "low maintenance"—and compared to asphalt shingles, they are. But "low maintenance" doesn't mean "no maintenance." For Myrtle Beach homeowners, regular cleaning is essential because our coastal environment creates unique challenges that accelerate roof deterioration.
1. Preserve Your Roof's Lifespan
A properly maintained metal roof lasts 40-70 years. But in coastal South Carolina, salt deposits, algae, and debris can reduce that lifespan to 25-40 years if you neglect cleaning. The difference? $20,000-$40,000 in premature replacement costs.
2. Maintain Curb Appeal & Property Value
A clean metal roof adds 5-8% to home resale value according to Remodeling Magazine. Conversely, a stained, algae-covered roof signals "deferred maintenance" to buyers and can reduce offers by 3-5%.
3. Prevent Water Damage
Debris accumulation traps moisture against the roof surface, accelerating corrosion and creating conditions for leaks. Hidden water damage from blocked drainage paths can cost $5,000-$15,000+ to repair.
4. Improve Energy Efficiency
Dirty roofs lose reflectivity. A clean metal roof reflects 85-90% of solar radiation, reducing cooling costs by 10-25%. A dirty roof may only reflect 60-70%, forcing your AC to work harder during Myrtle Beach's 95°F+ summers.
5. Protect Coating & Warranty
Metal roof coatings (PVDF, Kynar, painted finishes) require periodic cleaning to maintain warranty coverage. Neglected buildup can void manufacturer warranties worth $5,000-$15,000+.
8 Signs Your Metal Roof Needs Cleaning
Don't wait until problems become obvious. These warning signs indicate it's time to clean your metal roof:
1. Visible Debris Accumulation
Leaves, pine needles, branches in valleys and around penetrations
2. Green/Black Streaks
Algae, moss, or mildew growth (common on shaded roof sections)
3. White Chalky Residue
Salt deposits from ocean air (critical for coastal homes)
4. Rust Spots Appearing
Surface oxidation—clean immediately before corrosion spreads
5. Faded or Dull Appearance
Loss of original color vibrancy and reflectivity
6. Bird Droppings
Acidic waste that etches protective coatings if left untreated
7. Clogged Gutters Overflowing
Indicates significant roof debris affecting drainage
8. Water Staining on Ceilings
Debris-blocked drainage causing water infiltration—urgent attention needed
Safety Requirements (Critical—Read Before Starting)
WARNING: Roof Work Is Dangerous
Falls are the #1 cause of construction fatalities. Metal roofs are especially slippery when wet. If you're not comfortable with heights, lack proper safety equipment, or have a steep roof, hire a professional.
Call WeatherShield Roofing at (843) 877-5539 for safe, professional cleaning.
Essential Safety Equipment
- Safety harness with roof anchor: OSHA-compliant fall arrest system rated for your weight
- Non-slip rubber-soled shoes: Soft rubber soles grip metal better than hard-soled boots
- Safety glasses: Protect eyes from cleaning solutions and debris
- Rubber gloves: Chemical-resistant for handling cleaning solutions
- Ladder with stabilizers: Extend 3 feet above roofline, use standoff brackets
- Spotter/helper: Someone to hold ladder and monitor your safety
Weather Requirements
- Clean only when roof is dry—wet metal is extremely slippery
- Avoid temperatures above 85°F (cleaning solutions dry too quickly)
- No wind above 15 MPH (affects balance and spray direction)
- Overcast days are ideal (prevents solution from drying before rinsing)
- Check Myrtle Beach forecast—no rain expected for 4+ hours after cleaning
Roof Inspection Before Climbing
From the ground, inspect for visible damage, loose panels, or storm damage before climbing. If you see any structural issues, stop and call a professional.
Complete Supplies Checklist
DIY Metal Roof Cleaning Kit ($75-$200)
Cleaning Tools
- ☐ Garden hose with adjustable spray nozzle
- ☐ Pressure washer (1,200-1,500 PSI max, optional)
- ☐ Soft-bristle brush with extension pole (12-24 ft)
- ☐ Pump sprayer (2-4 gallon capacity)
- ☐ Leaf blower (for debris removal)
- ☐ 5-gallon bucket for mixing solutions
- ☐ Soft cloths or microfiber towels
Cleaning Solutions
- ☐ Dish soap (Dawn or similar, no chlorine)
- ☐ Oxygen bleach (OxiClean or sodium percarbonate)
- ☐ White vinegar (for salt deposits)
- ☐ Commercial metal roof cleaner (optional)
- ☐ Rust converter/inhibitor (if rust spots present)
Safety Gear
- ☐ Safety harness and roof anchors
- ☐ Non-slip rubber-soled shoes
- ☐ Safety glasses and rubber gloves
- ☐ Extension ladder with stabilizers
Best Cleaning Solutions for Metal Roofs
NEVER Use These Products on Metal Roofs:
- ❌ Chlorine bleach (sodium hypochlorite)—corrodes metal, damages coatings, voids warranties
- ❌ Ammonia-based cleaners—can react with aluminum and strip protective finishes
- ❌ Abrasive cleaners or steel wool—scratches coatings and accelerates corrosion
- ❌ Petroleum-based solvents—damages PVDF and painted finishes
- ❌ High-pressure settings (over 1,500 PSI)—dents panels and forces water under seams
Recommended Cleaning Solutions by Problem Type
| Problem | Solution Recipe | Dwell Time |
|---|---|---|
| General Dirt & Grime | 1/4 cup dish soap per gallon of water | 5-10 minutes |
| Algae & Mildew | 1 cup oxygen bleach per gallon of water | 15-20 minutes |
| Salt Deposits (Coastal) | 50/50 white vinegar and water | 10-15 minutes |
| Bird Droppings | Soak with water, then dish soap solution | 20-30 minutes |
| Tree Sap & Pollen | Rubbing alcohol (70%) spot treatment | 5 minutes |
| Surface Rust | Commercial rust converter (follow product directions) | Per product |
How to Clean Your Metal Roof: Complete 15-Step Process
Follow these steps in order for a safe, thorough, professional-quality cleaning. Total time: 3-5 hours for a typical 1,500-2,500 sq ft roof.
Phase 1: Preparation
Steps 1-5 • Estimated time: 1 hour
Step 1: Check Weather & Plan Your Day
Choose an overcast day with temperatures between 50-85°F. Check that no rain is forecast for at least 4 hours after you'll finish. In Myrtle Beach, early morning (7-10 AM) provides ideal conditions in summer.
Time: 5 minutes
Step 2: Ground-Level Inspection
Walk around your home and inspect the roof from the ground. Use binoculars if needed. Look for: visible damage, sagging sections, loose panels, debris accumulation, and stain patterns. Document problem areas with photos before climbing.
Time: 10-15 minutes
Step 3: Protect Landscaping & Entry Points
Cover plants and shrubs near the house with plastic sheeting. Move outdoor furniture away from the drip line. Close all windows and doors. Cover or plug outdoor electrical outlets. Ensure pets are secured indoors.
Time: 15-20 minutes
Step 4: Set Up Safety Equipment
Position your ladder at a 75-degree angle (1 foot out for every 4 feet up). Extend 3 feet above the roofline. Install roof anchors and connect your safety harness. Have your spotter in position. Test all connections before climbing.
Time: 15-20 minutes
Step 5: Close-Up Roof Inspection
Once safely on the roof, inspect for: loose or missing fasteners, damaged seams, rust spots, cracked sealant, debris in valleys, and soffit/fascia damage. If you find structural issues, stop and call (843) 877-5539.
Time: 15-20 minutes
Phase 2: Cleaning Process
Steps 6-10 • Estimated time: 1.5-2 hours
Step 6: Remove Loose Debris
Using a leaf blower or soft-bristle broom, clear all loose debris from the roof surface. Start at the ridge and work down toward the eaves. Pay special attention to valleys, around vents, skylights, and HVAC penetrations. Never use a metal rake or hard-bristle broom—they scratch coatings.
Time: 20-30 minutes
Step 7: Pre-Rinse the Entire Roof
Using a garden hose (or pressure washer at 1,200-1,500 PSI max), rinse the entire roof surface with clean water. Work from the ridge down, following the direction of water flow. This removes surface dirt and prepares the surface for cleaning solution.
Time: 15-20 minutes
Step 8: Apply Cleaning Solution
Using a pump sprayer, apply your cleaning solution in sections (approximately 10x10 feet at a time). Start at the lowest point and work up—this prevents solution from running onto already-cleaned areas. Apply generously, ensuring complete coverage.
Time: 20-30 minutes
Step 9: Allow Dwell Time
Let the cleaning solution work for 10-20 minutes depending on the type (see solution chart above). Critical: Don't let the solution dry on the roof. If it starts drying, mist with water to keep it wet. On hot days, work in smaller sections.
Time: 10-20 minutes
Step 10: Gentle Agitation for Stubborn Areas
Using a soft-bristle brush on an extension pole, gently scrub areas with visible staining, algae, or buildup. Work in the direction of the panel ribs (with the grain). Apply light pressure—let the cleaning solution do the work. Never use circular scrubbing motions.
Time: 20-40 minutes (varies by condition)
Phase 3: Rinsing & Finishing
Steps 11-15 • Estimated time: 1-1.5 hours
Step 11: Thorough Rinsing
Rinse the entire roof thoroughly with clean water, starting at the ridge and working down. Ensure ALL cleaning solution is removed—residue can leave streaks or damage coatings. Take extra time around seams, fasteners, and penetrations.
Time: 20-30 minutes
Step 12: Inspect & Repeat if Necessary
After rinsing, inspect for remaining stains or missed areas. For stubborn spots, repeat steps 8-11 with a stronger solution or longer dwell time. Some stains (particularly old rust or heavy algae) may require multiple treatments.
Time: 10-30 minutes (if needed)
Step 13: Clean Gutters & Downspouts
All the debris and cleaning solution runoff is now in your gutters. Clear all debris from gutters, flush downspouts with water, and ensure proper drainage. Clogged gutters negate much of the benefit of roof cleaning.
Time: 20-30 minutes
Step 14: Final Roof Inspection
With the roof now clean, conduct a thorough inspection for issues that weren't visible before: hairline rust, loose fasteners, failing sealant, or coating damage. Document any problems with photos for future reference or professional consultation.
Time: 15-20 minutes
Step 15: Ground Cleanup & Documentation
Safely descend from the roof. Remove protective coverings from landscaping. Rinse any cleaning solution from plants, siding, or concrete. Store equipment properly. Take "after" photos for your records and to compare at the next cleaning.
Time: 15-20 minutes
Myrtle Beach Coastal Considerations
Living in Myrtle Beach, North Myrtle Beach, Surfside Beach, or Garden City means your metal roof faces unique challenges that inland homeowners don't encounter:
Salt Air Corrosion
Ocean air carries salt particles that deposit on your roof constantly. Within 1 mile of the ocean, salt exposure accelerates corrosion by 5-10x compared to inland areas. Salt damage is the #1 enemy of coastal metal roofs.
- Prevention: Clean every 3-4 months (vs. 6-12 months inland)
- Treatment: Use vinegar-based solution to dissolve salt deposits
- Long-term protection: Consider protective roof coatings
High Humidity & Algae
Myrtle Beach's 75%+ average humidity creates perfect conditions for algae, mold, and mildew growth—especially on north-facing roof sections. The dark streaks you see on coastal roofs are typically Gloeocapsa magma, a cyanobacteria that feeds on limestone roof particles.
- Prevention: Install zinc or copper strips along the ridge
- Treatment: Oxygen bleach solution (never chlorine)
- Long-term: Algae-resistant roof coatings
Hurricane Season Preparation
Clean your metal roof before hurricane season (June-November). Debris left on the roof becomes dangerous projectiles in high winds. A clean roof also allows for better inspection of fasteners and seams that need reinforcement.
See our complete hurricane preparation guide for more details.
Considering a New Metal Roof?
If your current metal roof requires extensive repairs or you're looking to upgrade, consider metal roofs that look like shingles—stone-coated steel and architectural metal panels that combine 50+ year durability with traditional curb appeal perfect for Myrtle Beach HOAs.
Seasonal Cleaning Schedule for Myrtle Beach
| Season | Timing | Focus Areas | Priority |
|---|---|---|---|
| 🌸 Spring | Late April - Early May | Pollen removal, debris clearing, winter damage check | HIGH |
| ☀️ Summer | Early June (pre-hurricane) | Salt removal, fastener inspection, algae treatment | CRITICAL |
| 🍂 Fall | Late October - November | Leaf removal, gutter clearing, post-storm inspection | HIGH |
| ❄️ Winter | January - February (if needed) | Salt buildup inspection, spot cleaning only | MODERATE |
Beachfront Properties (Within 1 Mile of Ocean)
Add a quarterly salt inspection to this schedule. Check for white crystalline deposits after every significant storm event. Properties in Garden City, oceanfront Surfside Beach, and Cherry Grove should plan for 4 cleanings annually.
Troubleshooting Stubborn Stains
Some stains require specialized treatment. Here's how to handle the most common stubborn problems:
Rust Stains
Surface rust (orange-brown spots) indicates the protective coating has been compromised. Action required immediately to prevent spreading.
- Wire brush loose rust (gently, avoid scratching surrounding coating)
- Apply rust converter according to product instructions
- Wait for converter to cure (typically 24 hours)
- Apply matching touch-up paint or rust-inhibiting primer
- Consider professional roof coating if rust is widespread
Severe Algae/Mold (Black Streaks)
- Apply oxygen bleach solution at double strength (2 cups per gallon)
- Allow 30-45 minute dwell time (keep wet)
- Scrub with soft brush
- Rinse thoroughly
- Repeat if necessary
- Install zinc or copper strips at ridge to prevent regrowth
Oil/Grease Stains
Common near HVAC units, vents, or after roof work.
- Apply degreasing dish soap (Dawn is excellent) directly to stain
- Scrub gently with soft brush
- For stubborn grease, use isopropyl alcohol as a spot treatment
- Rinse thoroughly with water
Chalking (White Powder)
Chalking is normal oxidation of paint/coating surfaces, especially after 15+ years.
- Clean with soap and water solution
- If significant, indicates coating is nearing end of life
- Consider roof recoating to restore protection
DIY vs Professional Metal Roof Cleaning: Costs Compared
| Factor | DIY Cleaning | Professional Cleaning |
|---|---|---|
| Cost (1,500 sq ft roof) | $75-$200 (supplies) | $375-$750 |
| Time Investment | 4-6 hours | 2-3 hours (2-person crew) |
| Safety Equipment | Your responsibility ($200-$500+ if purchased) | Included (OSHA-compliant) |
| Liability/Insurance | Your homeowner's policy | Contractor's liability coverage |
| Damage Risk | Higher (inexperience) | Lower (trained technicians) |
| Results Quality | Good (with proper technique) | Excellent (professional equipment) |
| Includes Inspection | Basic (untrained eye) | Professional assessment included |
When to Call a Professional
DIY cleaning works well for routine maintenance on accessible, low-slope roofs. However, certain situations require professional expertise:
Call a Professional If:
- 🔴 Your roof pitch exceeds 6:12 (too steep for safe DIY work)
- 🔴 The roof is higher than 2 stories (increased fall risk)
- 🔴 You notice rust spots, corrosion, or coating damage
- 🔴 There's significant algae/mold coverage (30%+ of surface)
- 🔴 You lack proper safety equipment
- 🔴 You're uncomfortable working on roofs
- 🔴 The roof has complex geometry (multiple levels, valleys, dormers)
- 🔴 You see signs of storm damage
Get a Free Professional Assessment
WeatherShield Roofing offers free roof inspections for Myrtle Beach homeowners. Our 5.0★ rated team will assess your roof's condition, recommend appropriate cleaning methods, and identify any maintenance issues before they become expensive problems.
Call us today: (843) 877-5539
Prevention & Long-Term Care Tips
Reduce cleaning frequency and extend your metal roof's lifespan with these preventive measures:
1. Install Zinc or Copper Strips
Metal strips installed along the ridge release algae-killing ions when it rains. This prevents algae and moss growth for 10-20 years. Cost: $200-$500 installed.
2. Trim Overhanging Trees
Keep branches at least 10 feet from the roof surface. This reduces debris accumulation, limits shade (which promotes algae), and prevents abrasion damage during storms.
3. Maintain Gutters
Clean gutters at least twice yearly. Clogged gutters cause water backup that damages roof edges and accelerates corrosion on metal roofs.
4. Address Minor Issues Immediately
Small rust spots, loose fasteners, or cracked sealant should be addressed within weeks—not months. Small problems compound quickly in coastal environments.
5. Consider Protective Roof Coating
For roofs 10+ years old, a professional roof coating can add 10-20 years of life, improve energy efficiency by 10-25%, and make future cleaning easier.
6. Schedule Annual Professional Inspections
Even if you DIY clean, have a professional inspect your roof annually. They'll catch issues you might miss and can address problems before they require expensive repairs.
Frequently Asked Questions
How often should you clean a metal roof in coastal areas?
In Myrtle Beach and other coastal areas, metal roofs should be cleaned 2-3 times per year due to salt air exposure. Clean in spring (after pollen season), late summer (before hurricane season), and fall (after leaves drop). Homes within 1 mile of the ocean may need quarterly cleaning to prevent salt corrosion.
Can you pressure wash a metal roof?
Yes, but with extreme caution. Use only 1,200-1,500 PSI maximum pressure with a 25-40 degree wide-angle tip. Never use a zero-degree tip as it can dent panels, damage coatings, and void warranties. Keep the nozzle 12+ inches from the surface and spray at a downward angle to prevent water infiltration under seams.
What is the best cleaning solution for metal roofs?
For general cleaning, mix 1/4 cup dish soap per gallon of water. For algae and mildew, use oxygen bleach (sodium percarbonate) at 1 cup per gallon. For salt deposits, use a 50/50 white vinegar and water solution. Never use chlorine bleach, abrasive cleaners, or petroleum-based solvents as they damage protective coatings.
How much does professional metal roof cleaning cost?
Professional metal roof cleaning in Myrtle Beach typically costs between $0.25-$0.50 per square foot, or $375-$750 for a typical 1,500 sq ft roof. Factors affecting cost include roof pitch, accessibility, severity of buildup, and whether specialized treatments (rust inhibitors, algae prevention) are needed. DIY cleaning costs $75-$200 in supplies.
Will cleaning a metal roof damage the coating?
Proper cleaning will not damage metal roof coatings. However, using harsh chemicals (chlorine bleach, ammonia, abrasives), excessive pressure washing (over 1,500 PSI), or abrasive brushes can strip protective coatings and void warranties. Always use soft-bristle brushes, appropriate cleaning solutions, and gentle pressure.
How do you remove algae and mold from a metal roof?
To remove algae and mold: 1) Pre-rinse the roof, 2) Apply oxygen bleach solution (1 cup sodium percarbonate per gallon of water), 3) Let dwell for 15-20 minutes, 4) Gently scrub with soft brush, 5) Rinse thoroughly. For severe growth, use a commercial roof cleaner with zinc or copper additives. Installing zinc or copper strips at the ridge can prevent future growth.
When should you call a professional to clean your metal roof?
Call a professional if: your roof has a pitch steeper than 6:12, you notice rust spots or coating damage, there's significant algae/mold coverage, the roof is higher than 2 stories, you lack proper safety equipment, or you're uncomfortable working on roofs. Professionals have proper fall protection, insurance, and experience with coastal metal roofs.
Does cleaning a metal roof extend its lifespan?
Yes. Regular cleaning can extend metal roof lifespan by 5-10 years. Removing salt deposits prevents corrosion, clearing debris prevents moisture retention and rust, and eliminating algae/mold prevents coating degradation. In coastal South Carolina, regular cleaning is essential—neglected metal roofs can fail 15-20 years earlier than properly maintained ones.
Get Your Free Metal Roof Inspection
WeatherShield Roofing provides free, no-obligation roof inspections for Myrtle Beach homeowners. Our 5.0★ rated experts will assess your metal roof's condition, identify any issues, and recommend the best maintenance plan for your home.
Related Articles
Roof Coating for Metal Roof: Complete 2025 Guide
Extend your metal roof's life by 10-20 years with the right coating system.
How Salt Air Destroys Coastal Roofs (And 7 Ways to Fight Back)
Protect your investment from Myrtle Beach's corrosive salt environment.
Metal Roofing for Hurricane Protection: Complete Guide
Learn why metal roofs rated to 180 MPH are ideal for coastal SC homes.
Standing Seam vs Corrugated Metal Roof: 15 Critical Factors
Compare metal roof styles for Myrtle Beach coastal homes.