For South Jersey homeowners in places like Cherry Hill, Marlton, and Deptford, understanding what supports your shingles—and how it protects your home—is critical when considering a roof replacement.
In this complete guide, we break down what roof sheathing is, how to choose the right type, and why it plays such a vital role in your home’s roofing system.
What Is Roof Sheathing?
Roof sheathing, also called roof decking, is the flat panel material that covers the structural framing of your roof. It creates a solid, continuous surface that supports underlayment and shingles—forming the foundation of your roofing system.
At RGB Construction, we often explain to homeowners that the sheathing is the bridge between your home’s structure and its layer of protection from the elements.
Proper sheathing ensures a solid, secure foundation for shingles.
Why Roof Sheathing Matters in a Roofing System
Sheathing is more than a structural layer—it’s a critical part of your roof’s performance.
- Provides a secure surface for shingle fastening
- Increases wind resistance and prevents uplift
- Improves waterproofing by minimizing gaps
- Helps distribute weight evenly across your roof
- Reduces the risk of leaks and sagging
A well-installed roof sheathing layer is essential for maximizing the lifespan of your asphalt shingles and preserving the structural integrity of your home.
Learn more about roof water damage and prevention »
OSB vs. Plywood: Which Is Best for NJ Homes?
In South Jersey, most roof sheathing is made from wood panels, with OSB (Oriented Strand Board) and CDX plywood being the most popular choices.
| Feature | OSB | Plywood |
|---|---|---|
| Weight | Lighter | Slightly heavier |
| Cost | Lower | Higher |
| Durability | Strong, resists bending | Stronger under heavy roofing materials |
| Water Resistance | Moderate | Better |
| Best Use | Asphalt shingles, budget-conscious roofs | Tile, metal, concrete roofs or humid climates |
At RGB, we help homeowners choose based on roofing material weight, climate, and budget.
OSB vs. Plywood: See our detailed comparison »
Roof Sheathing Thickness & Roof Pitch
Sheathing panels typically range between ⅜” and ⅝” thick. The ideal thickness depends on your roof’s pitch (slope):
| Roof Pitch | Recommended Thickness |
|---|---|
| Steep Slope | ⅜” to ½” (lighter weight) |
| Low Slope / Flat | ½” to ⅝” (stronger support) |
Flat and low-slope roofs in NJ may require thicker sheathing to handle standing water and snow accumulation.
Do Older Homes Have Roof Sheathing?
If your home was built before the 1950s, there’s a good chance it lacks modern sheathing. Instead, older homes often have plank decking—wood boards spaced apart under shingles.
This setup increases the risk of:
- Leaks from underlayment gaps
- Nail pops
- Shingle warping or blow-off
Retrofitting with solid sheathing greatly improves protection and supports GAF roofing system warranties.
Do you have rotted or outdated roof decking? Find out here »
Common Signs of Damaged Sheathing
If you notice any of these warning signs, it may be time to inspect your roof sheathing:
- Sagging areas or waves on the roofline
- Water stains on ceiling or attic rafters
- Mold or mildew smells in the attic
- Soft or spongy areas when walking on the roof
- Missing shingles and consistent roof leaks
These symptoms often mean the sheathing has become weakened by water intrusion or rot.
How Sheathing Affects Asphalt Shingle Performance
Modern asphalt shingles require a flat, dry, and properly ventilated surface to perform at their best. Poor sheathing installation leads to:
- Nail pull-through
- Uneven surfaces and shingle lifting
- Shortened roof lifespan
- Voided warranties
As a GAF Master Elite® Contractor, RGB Construction ensures your sheathing meets GAF standards to qualify for enhanced system warranties.
A completed residential roof in South Jersey showing high-performance shingles installed over expertly placed OSB roof sheathing.
FAQs About Roof Sheathing
- Q: Can I reuse my existing sheathing during a roof replacement?
- A: Only if it’s free of moisture damage, warping, and mold. We inspect all sheathing before recommending reuse.
- Q: What’s the best sheathing material for heavy roofing like tile or concrete?
- A: We recommend CDX plywood due to its superior load-bearing capacity.
- Q: How much does it cost to replace roof sheathing in NJ?
- A: It depends on thickness, material, and roof size—but expect $1.50–$3.50 per sq. ft. installed.
- Q: Do I need sheathing if my home has spaced planks?
- A: Yes, if you’re upgrading to modern shingles or want to prevent leaks and improve energy efficiency.
Book a Free Roof Sheathing Inspection Today
Whether you’re planning a full roof replacement or just want peace of mind, RGB Construction offers free inspections for homeowners throughout Camden, Gloucester, and Burlington Counties.
Schedule My Free Sheathing Evaluation »
Or call us now at 856-264-9093
Ask about our lifetime shingle warranties and seasonal offers!
Final Note from RGB Construction
At RGB Construction, Excellence isn’t just the goal—it’s the standard.
From our initial inspection to the final nail, we build roofs that protect your home, your investment, and your family—for decades to come.
