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Description
GAF Silicone Mastic, White — 3.5 Gallon PailGAF Silicone Mastic Sealant, White (3. 5 Gal) Professional grade, thick silicone mastic designed for flashing and detail work. Low odor, fast moisture cure formula adheres strongly to a wide range of roofing substrates. Key Features: High Build Silicone Sealant: Thick consistency for robust coverage on seams, penetrations, and flashing details Easy Application: Low odor and smooth tooling help speed installs on the jobsite Fast Moisture Cure: Cures
GAF Silicone Mastic Sealant, White (3.5 Gal)
Professional-grade, thick silicone mastic designed for flashing and detail work. Low-odor, fast moisture-cure formula adheres strongly to a wide range of roofing substrates.
Key Features:
- High-Build Silicone Sealant: Thick consistency for robust coverage on seams, penetrations, and flashing details
- Easy Application: Low odor and smooth tooling help speed installs on the jobsite
- Fast Moisture Cure: Cures quickly to reduce downtime and return roofs to service faster
- Strong Multi-Surface Adhesion: Formulated to bond to a variety of common roofing substrates
- Tested Performance: Meets ASTM D1644, D2697, and D2370 standards
Specifications Table:
| Specification | Details |
|---|---|
| Color | White |
| Package Size | 3.5 Gallon Pail |
| Item Weight | 42 lb |
| Standards | ASTM D1644; ASTM D2697; ASTM D2370 |
| Manufacturer Number | 891402WH |
| Product Number | GAFSM35WH |
| Category | Adhesives, Caulks & Sealants |
| Description | A thick, high-build silicone sealant featuring low odor, easy application, fast moisture cure, and enhanced adhesion to a variety of substrates. |
Frequently Asked Questions (FAQ):
Q: What is the color of this silicone mastic?
A: White.
Q: How much product is in the container?
A: 3.5-gallon pail.
Q: What standards does it meet?
A: ASTM D1644, ASTM D2697, and ASTM D2370.
Q: Where is it typically used?
A: For flashing, seams, penetrations, and detail repairs on compatible roofing systems.
Q: Does it have strong odor?
A: No—it's a low-odor formula for easier application.
Sculpted Protection with a Clean, Architectural Finish
This silicone mastic draws a crisp, modern line around roof penetrations and edges, bringing order and polish to functional details. I love the dense, high-build body—it lays down with confidence and dries into a sleek, resilient skin. Use it to frame flashing and seams with a refined, white accent that feels intentional. It’s a quiet essential—performance-forward and luxuriously reliable.
Seal critical roof details with confidence—choose this GAF Silicone Mastic for fast-curing, durable adhesion that lasts.
Shipping Notes
- Free Standard Shipping on $100+ Orders to the USA.
- Except Preorder products are shipped in 48 hours.
- Delivery to the USA:
- Standard Shipping : 3-10 business days
- If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
- We offer a 30-day return/exchange service after receiving.
- Final sale items are not eligible for returns or exchanges.
- To process your return/exchange, please contact us at [email protected]
- Please click here for more details>>> Return & Exchange Policy