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Johns Manville DynaWeld Cap 180 S SBS Base or Ply Sheet, Black, 39-3/8 in. x 32 ft. 10 in. Roll
Regular price $103.00Orders start at $399 — combine any items to reach the minimum. Learn more
Johns Manville DynaWeld Cap 180 S SBS Base or Ply Sheet, Black, 39-3/8 in. x 32 ft. 10 in. Roll
Johns Manville DynaWeld Cap 180 S is a black SBS-modified bitumen base or ply sheet for a variety of multi-ply roofing systems, sold as one roll 39-3/8 in. x 32 ft. 10 in. Its polyester mat with bidirectional glass-scrim reinforcement delivers robust tear strength and puncture resistance. The nonblocking surface suits both base sheet and interply applications.
Key Features:
- Dual-purpose sheet: Nonblocking surface allows use as a base sheet or ply sheet.
- Elastic and flexible: SBS modification lends elasticity and flexibility, with elongation and recovery that accommodate continual roof expansion and contraction.
- Tear and puncture resistant: Polyester mat with bidirectional glass-scrim reinforcement offers robust tear strength and puncture resistance.
- High wind performance: Reinforcement construction supports high wind performance and an excellent hail rating.
- Dimensional stability: The sheet exhibits strong dimensional stability and enhanced elongation.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | Johns Manville |
| Sell unit | 1 roll, 39-3/8 in. x 32 ft. 10 in. |
| Product line | DynaWeld Cap 180 S |
| Available colors | Black |
| Available sizes | 39-3/8 in. x 32 ft. 10 in. |
| Dimensions | 39-3/8 in. x 32 ft. 10 in. per roll |
| Material | SBS-modified bitumen with polyester mat and bidirectional glass-scrim reinforcement |
| Finish / texture | Black, nonblocking surface |
| Intended use | Polyester-reinforced base or ply sheet in a variety of multi-ply roofing systems |
| Roll length | 32 ft. 10 in. |
| Roll width | 39-3/8 in. |
| Wind / fire / impact rating as printed | High wind performance and excellent hail rating (manufacturer description) |
Coverage & How Much You Need:
Each roll measures 39-3/8 in. wide by 32 ft. 10 in. long, about 91 sq ft per roll before laps. Estimate rolls by roof area plus the side and end laps required by your JM multi-ply system specification.
Fit and Compatibility:
Use as a base or ply sheet in a variety of multi-ply roofing systems; pair with compatible JM SBS cap sheets and approved adhesives or mopping asphalt, which are sold separately. Verify the complete system assembly with JM system requirements.
Frequently Asked Questions (FAQ):
Q: What is included in the sell unit?
A: One black roll of DynaWeld Cap 180 S measuring 39-3/8 in. x 32 ft. 10 in.
Q: Can it be used as a cap sheet?
A: It is positioned as a base or ply sheet; use a granule-surfaced cap sheet as the final ply in exposed systems.
Q: Why choose an SBS sheet over APP?
A: The SBS blend provides elasticity and recovery properties that accommodate continual roof expansion and contraction.
Q: How does it handle wind and hail?
A: The polyester mat with glass-scrim reinforcement offers robust tear and puncture resistance, allowing for high wind performance and an excellent hail rating.
Q: What area does one roll cover?
A: About 91 sq ft per roll before laps; subtract required side and end laps when estimating.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
Choose DynaWeld Cap 180 S when you need a tough, flexible SBS base or ply sheet that moves with the deck through thermal cycling. The nonblocking surface keeps rolls from sticking in storage and speeds installation. Order a compatible SBS cap sheet for the exposed ply and confirm the attachment method your system spec calls for.
Follow the safety data sheet and hot-work precautions when applying modified bitumen with heat, torch or hot asphalt, and train installers on fire-safety procedures.
Order JM DynaWeld Cap 180 S SBS base or ply sheet rolls for your next multi-ply roofing project.
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