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Fontana Paper Mill VulcaSeal G40 Fiberglass Modified Tile & Metal Roof Underlayment - 2 Square Roll
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Fontana Paper Mill VulcaSeal G40 Fiberglass Modified Tile & Metal Roof Underlayment - 2 Square Roll
Fontana Paper Mill VulcaSeal G40 is a fiberglass-reinforced modified underlayment for tile and metal roofs, supplied as a 2 square roll covering 216 sq ft. It meets ASTM D6757-02 and ASTM D4601-98 and is listed as a UL Type II Glass Base Sheet. One roll is the sell unit.
Key Features:
- Fiberglass Reinforced: A fiberglass mat gives the sheet dimensional stability and tear resistance under tile and metal roofing.
- Modified Formula: Modified asphalt construction provides a tougher, more weather-resistant layer than standard felts.
- Tile & Metal Rated: Designed specifically as underlayment beneath tile and metal roof systems.
- 216 sq ft Roll: Each 2 square roll covers 216 sq ft, allowing for standard side and end laps.
- Code Listed: Meets ASTM D6757-02 and ASTM D4601-98; UL Type II Glass Base Sheet; UL ER 18554-01.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | Fontana Paper Mill |
| Sell unit | 1 roll, 2 squares (216 sq ft) |
| Product line | VulcaSeal G40 |
| Dimensions | 216 sq ft per roll (2 squares) |
| Coverage per unit | 216 sq ft (2 SQ per roll) |
| Material | Fiberglass-reinforced modified underlayment |
| Approvals | ASTM D6757-02; ASTM D4601-98; UL Type II Glass Base Sheet; UL ER 18554-01 |
| Intended use | Underlayment for tile and metal roof systems |
| Weight | 83.33 lb. per roll |
Coverage & How Much You Need:
One roll covers 216 sq ft, rated at 2 squares per roll. When laps are included, the net installed area is less than the roll's nominal area, so plan lap allowances per the tile or metal manufacturer's instructions.
Fit and Compatibility:
Intended for use under tile and metal roofing systems as a code-listed underlayment layer. Fasten with cap nails such as Grip-Rite Grip-Cap and seal laps per the roof system manufacturer's details; roofing and fasteners sold separately.
Frequently Asked Questions (FAQ):
Q: How much area does one roll cover?
A: Each roll is rated at 2 squares, covering 216 sq ft; deduct lap allowances from installed coverage.
Q: What roofs is it designed for?
A: It is a fiberglass modified underlayment made for tile and metal roof systems.
Q: How should it be fastened?
A: Fasten per the roof system manufacturer's instructions, typically with cap nails spaced to hold the sheet flat.
Q: What standards does it meet?
A: It meets ASTM D6757-02 and ASTM D4601-98, is a UL Type II Glass Base Sheet, and is listed under UL ER 18554-01.
Q: How heavy is a roll?
A: The roll weighs approximately 83 lb., so use two people or mechanical handling to move it.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
For tile and metal roofs, a fiberglass modified sheet like VulcaSeal G40 gives better tear resistance and secondary water protection than organic felts. Run it over the deck with laps shingled so water sheds down-slope, and keep the sheet flat with the specified cap-nail pattern. Confirm the assembly with the covering roof manufacturer's requirements, as warranty approval often depends on the specified underlayment.
Roll out and fasten underlayment carefully on pitched decks; wear fall protection per OSHA and keep feet clear of the roll edge.
Order VulcaSeal G40 fiberglass modified underlayment by Fontana Paper Mill for your next tile or metal roof.
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