
GAF EverGuard WaterBlock Mastic, Black – 10.5 oz Cartridge
EverGuard WaterBlock Butyl Mastic Sealant
One-part, butyl-based high-viscosity mastic designed for commercial roofing sealant applications. Ideal for sealing between flashing membranes and substrates behind termination bars, and between roofing membranes and drain flanges.
Key Features:
- Butyl-Based Formula: Provides strong, durable sealing for roofing details
- High-Viscosity Mastic: Stays in place for reliable water-blocking performance
- Targeted Roofing Use: For flashing terminations and drain flange interfaces
- Cartridge Convenience: 10.5 oz cartridge fits standard caulk guns
- Color: Black for discreet, professional finishes
Specifications Table:
| Specification | Details |
|---|---|
| Brand | GAF |
| Product Line | EverGuard |
| Product Name | WaterBlock Mastic |
| Color | Black |
| Composition | One-part butyl-based mastic |
| Viscosity | High-viscosity |
| Packaging | 10.5 oz cartridge |
| Intended Use | Sealing between flashing membrane and substrate behind termination bars; sealing between roofing membrane and drain flanges |
| Pieces per Carton | 25 |
| Style Category | Adhesives, Caulks & Sealants |
Frequently Asked Questions (FAQ):
Q: Is this mastic compatible with TPO roofing systems?
A: Yes, it is intended for use with EverGuard and similar single-ply roofing details per product description.
Q: Where should I apply it?
A: Use between flashing membrane and substrate behind termination bars, and between roofing membrane and drain flanges.
Q: Is it a single-component product?
A: Yes, it is a one-part butyl-based sealant; no mixing required.
Q: What size is the cartridge?
A: 10.5 oz cartridge.
Q: What color is the mastic?
A: Black.
Seamless Strength for Rooftop Details
This mastic delivers a crisp, professional finish while quietly fortifying the most vulnerable roof transitions. Its dense butyl body clings with conviction, creating a clean, confident seal at terminations and drains. Pair it with sleek metal flashing and precision-applied membranes for a refined, high-performance edge detail. It’s a discreet essential that elevates both the look and longevity of a roof—true luxury in function.
Seal critical roof transitions with confidence—choose EverGuard WaterBlock Mastic for durable, professional results.
Original: $8.51
-70%$8.51
$2.55Product Information
Product Information
Shipping & Returns
Shipping & Returns
Description
EverGuard WaterBlock Butyl Mastic Sealant
One-part, butyl-based high-viscosity mastic designed for commercial roofing sealant applications. Ideal for sealing between flashing membranes and substrates behind termination bars, and between roofing membranes and drain flanges.
Key Features:
- Butyl-Based Formula: Provides strong, durable sealing for roofing details
- High-Viscosity Mastic: Stays in place for reliable water-blocking performance
- Targeted Roofing Use: For flashing terminations and drain flange interfaces
- Cartridge Convenience: 10.5 oz cartridge fits standard caulk guns
- Color: Black for discreet, professional finishes
Specifications Table:
| Specification | Details |
|---|---|
| Brand | GAF |
| Product Line | EverGuard |
| Product Name | WaterBlock Mastic |
| Color | Black |
| Composition | One-part butyl-based mastic |
| Viscosity | High-viscosity |
| Packaging | 10.5 oz cartridge |
| Intended Use | Sealing between flashing membrane and substrate behind termination bars; sealing between roofing membrane and drain flanges |
| Pieces per Carton | 25 |
| Style Category | Adhesives, Caulks & Sealants |
Frequently Asked Questions (FAQ):
Q: Is this mastic compatible with TPO roofing systems?
A: Yes, it is intended for use with EverGuard and similar single-ply roofing details per product description.
Q: Where should I apply it?
A: Use between flashing membrane and substrate behind termination bars, and between roofing membrane and drain flanges.
Q: Is it a single-component product?
A: Yes, it is a one-part butyl-based sealant; no mixing required.
Q: What size is the cartridge?
A: 10.5 oz cartridge.
Q: What color is the mastic?
A: Black.
Seamless Strength for Rooftop Details
This mastic delivers a crisp, professional finish while quietly fortifying the most vulnerable roof transitions. Its dense butyl body clings with conviction, creating a clean, confident seal at terminations and drains. Pair it with sleek metal flashing and precision-applied membranes for a refined, high-performance edge detail. It’s a discreet essential that elevates both the look and longevity of a roof—true luxury in function.
Seal critical roof transitions with confidence—choose EverGuard WaterBlock Mastic for durable, professional results.






















