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Johns Manville GlasBase Plus SBS Modified Bitumen Base Sheet, 3 Square Roll
Regular price $139.58Orders start at $399 — combine any items to reach the minimum. Learn more
Johns Manville GlasBase Plus SBS Modified Bitumen Base Sheet, 3 Square Roll
Johns Manville GlasBase Plus is an SBS-modified bitumen membrane with a glass fiber reinforcement, used as a base sheet in built-up and modified bitumen roof systems. It is sold as a 3-square roll. It works with JM BUR and modified bitumen system components.
Key Features:
- SBS modified: SBS-modified bitumen formulation for flexibility and durability.
- Glass reinforcement: Glass fiber reinforcement provides dimensional stability.
- Base sheet use: Designed as a base sheet for BUR and modified bitumen assemblies.
- 3 square roll: Each roll covers approximately 3 squares of roof area.
- Fastening patterns: JM publishes fastening pattern documents for tape-and-staple attached base applications.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | Johns Manville |
| Sell unit | 1 roll, 3 squares |
| Product line | GlasBase Plus |
| Material | SBS modified bitumen with glass fiber reinforcement |
| System type | BUR / SBS modified bitumen base sheet |
| Coverage per unit | 3 squares per roll |
| Intended use | Base sheet in low-slope commercial roofing |
| Approvals | See JM system approvals for the specified assembly |
Coverage & How Much You Need:
One roll covers approximately 3 squares (300 sq ft) before lapping. Account for head and side laps per JM fastening patterns when estimating rolls.
Fit and Compatibility:
Part of Johns Manville BUR and modified bitumen roofing systems; use with JM plies, adhesives and cap sheets per system specifications. Fastening per JM published patterns.
Frequently Asked Questions (FAQ):
Q: What is included?
A: One roll of GlasBase Plus covering about 3 squares.
Q: How do I size the order?
A: Divide roof area by 3 squares per roll and add for laps and waste.
Q: How is it attached?
A: It can be stapled or tape-attached following JM's published fastening patterns.
Q: Is it for low-slope roofs?
A: Yes, it is a commercial low-slope base sheet membrane.
Q: Does it require a cap sheet?
A: Yes, it serves as a base ply beneath JM cap membranes in a complete system.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
GlasBase Plus is a workhorse base ply for SBS systems; choose it where a glass-reinforced base with proven fastening patterns is needed. Follow JM's fastening pattern documents exactly for the deck type and wind exposure to maintain system approval. Order extra for laps and patches.
Handle hot asphalt or mechanical fastening equipment per safety guidelines and wear appropriate PPE during installation.
Order Johns Manville GlasBase Plus base sheet rolls for your next BUR or SBS system.
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