Roof Decking Damage Signs: Myrtle Beach Guide
Shocking Industry Truth
Most homeowners focus on their shingles—but underneath those shingles lies a critical component that determines your roof's structural integrity: the roof decking (also called roof sheathing). When decking fails, it doesn't matter how new your shingles are—your roof won't protect your home.
In Myrtle Beach's humid coastal climate, roof decking damage is more common than you might think. High humidity, storm damage, and poor ventilation can all lead to decking failure. This guide will help you recognize the warning signs before small problems become major structural issues.
At WeatherShield Roofing, we're 5.0-star rated on Google (81 reviews) and GAF Master Elite certified. We thoroughly inspect decking on every project because we know that a roof is only as good as its foundation.
Worried About Your Roof Decking?
If you've noticed sagging, soft spots, or water stains in your attic, your decking may be compromised. Call (843) 877-5539 for a free inspection—catching decking problems early can save thousands in repair costs.
Ready to Protect Your Investment?
Schedule your free roof inspection today. No obligations, just peace of mind.
What Is Roof Decking?
Roof decking is the structural layer between your roof's framing (trusses or rafters) and your roofing materials (underlayment and shingles). It provides the solid surface that everything else attaches to.
Types of Roof Decking
Plywood
- Made from thin wood layers glued together
- Better moisture resistance than OSB
- More expensive but preferred in coastal areas
- Typical thickness: 1/2" to 5/8"
OSB (Oriented Strand Board)
- Made from compressed wood strands and adhesive
- Less expensive than plywood
- More susceptible to moisture damage
- Common in newer construction
Why Decking Matters
Your roof decking serves several critical functions:
- Structural support: Bears the weight of roofing materials and people walking on the roof
- Nailing surface: Provides solid attachment for shingles and underlayment
- Weather barrier base: Creates continuous surface for waterproofing layers
- Wind resistance: Helps shingles resist uplift forces
Signs of Roof Decking Damage
Knowing what to look for can help you catch decking problems before they lead to major structural damage or interior water damage.
Visible Signs from Outside
- Sagging roof sections: Visible dips or waves in the roof surface, especially between rafters
- Uneven roof lines: Ridge line or edges that aren't straight
- Soft spots when walking on roof: Areas that flex or feel spongy underfoot (caution: don't walk on a potentially damaged roof)
- Shingles not laying flat: Bumps or ripples from warped decking underneath
Signs from the Attic
- Daylight through roof boards: Any light coming through is a serious sign
- Water stains on decking: Dark spots or discoloration
- Visible rot or mold: Especially common in humid SC climate
- Sagging between rafters: Decking bowing down between supports
- Delamination: Plywood layers separating (looks like peeling)
- OSB swelling: Edges that look puffy or expanded
Interior Warning Signs
- Ceiling water stains: Often indicate long-term moisture problems affecting decking
- Musty odors: Can indicate hidden mold from decking moisture
- Peeling paint on ceilings: Moisture migrating through damaged areas
What Causes Roof Decking Damage?
Understanding what damages decking helps you prevent future problems and understand why repairs are needed.
Water Infiltration
The most common cause. Water gets through damaged shingles, failed flashing, or ice dams and soaks into the decking. Over time, this leads to rot, mold, and structural weakness.
Poor Ventilation
In Myrtle Beach's humid climate, inadequate attic ventilation is a major problem. Moisture from inside the home rises into the attic. Without proper ventilation, this moisture condenses on the decking, causing gradual deterioration.
Coastal SC Ventilation Challenge
Our high humidity means ventilation is even more critical here than in drier climates. Many older Myrtle Beach homes have inadequate ventilation that was acceptable when built but doesn't meet current standards for our climate.
Age and Weathering
Even without leaks, decking deteriorates over time. OSB is particularly susceptible to edge swelling from humidity. Most decking should be inspected after 20-30 years.
Hurricane and Storm Damage
High winds can lift shingles, allowing water intrusion. Flying debris can puncture through to the decking. Storm surge or flooding can soak decking from below.
Improper Installation
Decking installed without proper gaps for expansion, with incorrect nailing patterns, or using wrong thickness can fail prematurely.
Can Roof Decking Be Repaired or Must It Be Replaced?
The answer depends on the extent and location of the damage.
When Partial Replacement Works
- Damage is limited to a small area (one or a few sheets)
- Surrounding decking is still solid
- No structural damage to rafters/trusses
- Moisture source has been identified and fixed
When Full Replacement Is Needed
- Widespread damage across multiple areas
- Extensive rot or mold throughout
- Decking age and condition make spot repairs impractical
- Building code requires it for re-roofing
Cost Factors
Decking replacement costs depend on:
- Amount of decking being replaced
- Material choice (plywood vs OSB)
- Accessibility of the damaged areas
- Whether rafter/truss repair is also needed
- Disposal of damaged materials
Contact WeatherShield at (843) 877-5539 for an honest assessment of your decking condition and repair options.
Roof Decking Materials: Plywood vs OSB
If you need decking replacement, understanding the material options helps you make an informed decision.
| Factor | Plywood | OSB |
|---|---|---|
| Moisture Resistance | Better | More susceptible |
| Cost | Higher | Lower |
| Nail Holding | Excellent | Good |
| Weight | Lighter | Heavier |
| Best For | Coastal areas, high humidity | Budget-conscious, inland |
Our Recommendation for Myrtle Beach
For coastal South Carolina, we generally recommend CDX plywood over OSB due to its superior moisture resistance. The additional cost is worthwhile insurance against our humid climate and storm exposure. If OSB is used, it should be a moisture-resistant variety specifically rated for humid environments.
How WeatherShield Handles Roof Decking Issues
At WeatherShield, we take decking seriously because we know it's the foundation of every quality roof installation.
Our Inspection Process
- Visual inspection from ground and attic
- Physical testing for soft spots and structural integrity
- Moisture meter readings to identify hidden water damage
- Documentation with photos for your records
- Honest assessment—we only replace what needs replacing
Our Commitment
- Free inspections—no obligation or pressure
- Transparent pricing for any decking work needed
- Quality materials appropriate for coastal conditions
- Proper installation per manufacturer and code requirements
- Warranty coverage on our workmanship
Schedule your free roof and decking inspection: (843) 877-5539
The Cost Comparison: Maintenance vs. Neglect
Without Maintenance
- Roof lifespan: 12-15 years
- Insurance claims often denied
- Emergency repairs cost 3x more
- Property value decreases by 5-10%
- Warranty becomes void
- Total 20-year cost: $35,000+
With Regular Maintenance
- Roof lifespan: 25-30+ years
- Insurance claims approved
- Prevent costly emergencies
- Property value protected
- Full warranty coverage maintained
- Total 20-year cost: $8,000-10,000
Don't Wait Until It's Too Late
Every day you delay costs you money. Get your FREE professional roof inspection today and discover exactly what condition your roof is in.
Emergency? Call our 24/7 hotline: (843) 877-5539
Frequently Asked Questions
About the Author
David Karimi
Owner & Lead Roofing Contractor
David Karimi is WeatherShield Roofing's owner with over 18 years of experience in residential and commercial roofing. A GAF Master Elite certified contractor, David has replaced thousands of damaged roof decking sections across the Grand Strand and understands the unique moisture challenges in coastal South Carolina.
The Bottom Line: Your Roof, Your Choice
Every day you wait is another day closer to that emergency call no homeowner wants to make. The statistics are clear: 80% of roofs fail prematurely, and 61% of homeowners can't afford the emergency repairs that follow.
What You Get with Weather Shield Roofing:
Don't Wait Until It's Too Late
Join thousands of smart Myrtle Beach homeowners who protect their investment with regular maintenance.
Emergency? Call our 24/7 hotline: (843) 877-5539
Our Roofing Services
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