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if you find an equal or better quality product at a lower price, we’ll beat that price by 10%!
VanBoxel SealShield™ — The First Nail-Sealable Synthetic Underlayment
When Only the Best Will Do.
Meet SealShield™, the next generation of roofing underlayment — the first synthetic underlayment certified to the nail-sealable standard ASTM D1970.
Engineered for premium roofing systems and demanding installers who settle for nothing less than perfection.
Unmatched Performance. Unrivaled Protection.
SealShield™ combines cutting-edge multi-layer construction with extreme durability and safety in mind. Every square foot is built to grip, seal, and protect — no matter what nature throws your way.
✅ ASTM D1970 Certified Nail Sealability – the gold standard for watertight protection.
✅ ASTM E108 Class A Fire Rating – top-tier flame resistance for maximum safety.
✅ ICC-ES AC188 & Intertek Code Compliant – tested and approved beyond expectations.
✅ Florida & Miami-Dade Approved – designed for hurricane-level resilience.
✅ UV Resistant up to 180 Days – built to handle extended exposure without degradation.
Premium Features for Premium Roofs
Multi-Layered Polypropylene Construction for superior strength and flexibility.
Anti-Slip Polyolefin Coating for maximum grip on steep slopes.
Tear-Resistant Reinforced Scrim prevents stretching, wrinkling, and warping.
100% Water & Air Resistant – creates a true secondary moisture barrier.
Mold & Odor Resistant – no mildew, no buckling, no compromises.
Lightweight Design – easier handling without sacrificing strength.
Built for Every Roof Type
Ideal for metal, fiberglass, asphalt, modified bitumen, tile, and slate roofing systems.
SealShield™ delivers elite performance for every premium application.
Product Specifications
| Specification | ASTM Standard | Typical Value |
|---|---|---|
| Nominal Thickness | D5261 | 32 mil |
| Finished Weight | D3776 | 270 g/m² |
| Tensile Strength | D751 | 51 lb MD / 33 lb CD |
| Elongation | D751 | 45% MD / 41% CD |
| Tear Resistance | D4533 | 27 lb MD / 25 lb CD |
| Temp Range | — | -40°F to 240°F |
| COF (Slip Resistance) | D1894 | 0.7 Top / 0.7 Bottom |
| Permeability | E96 | 0.01 perms Pass |
| Fire Rating | E108 | Class A |
Availability
Roll Size: 48″ x 125′ (5 sq. roll, 27 lb)
Packaging: 25 rolls per pallet
Printing: Up to 4-color high-quality printing
Private Label: Available with custom sizes and logos
SealShield™ — The Future of Roofing Protection
From blistering heat to freezing cold, SealShield™ is engineered to outlast, outperform, and outshine every other synthetic underlayment on the market.
When you’re building a roof that has to stand the test of time, there’s only one choice.
🔥 The First Nail-Sealable Synthetic. The Last Underlayment You’ll Ever Need.
VanBoxel SealShield™ — For Roofers Who Demand the Best.
