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RM Lucas #779 All-Weather Flashing Cement, Black, 3 Gal Mid-Season Grade
Regular price $37.00Orders start at $399 — combine any items to reach the minimum. Learn more
RM Lucas #779 All-Weather Flashing Cement, Black, 3 Gal Mid-Season Grade
RM Lucas #779 All-Weather Flashing Cement is a premium grade, trowel-applied black flashing cement sold as a 3-gallon mid-season grade unit. Made from higher softening point asphalt, petroleum solvents, reinforcing fibers and a water displacing additive, it installs, repairs and rebuilds flashings even on wet or underwater surfaces.
Key Features:
- All-weather application: Can be applied to wet and underwater surfaces, so repairs do not have to wait for dry conditions.
- Premium grade formula: Manufactured from higher softening point asphalt, petroleum solvents, reinforcing fibers and a special water displacing additive.
- Smooth trowel work: Applies fast and smooth and breaks cleanly off the trowel without stringing.
- Permanent repairs: May be used with fiberglass, polyester fabrics or roll roofing for permanent flashing repairs.
- Versatile flashing use: Used to install, repair or rebuild roof flashings at parapet walls, gravel stops, stacks, vents, monitors and similar applications.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | RM Lucas |
| Sell unit | 3-gallon unit |
| Product line | RM Lucas #779 All-Weather Flashing Cement |
| Material | Higher softening point asphalt with petroleum solvents, reinforcing fibers and water displacing additive |
| Color / finish | Black |
| Available colors | ['Black'] |
| Available sizes | ['3 gal Mid-Season Grade'] |
| Application method | Trowel-applied |
| Intended use | Installing, repairing or rebuilding roof flashings at parapet walls, gravel stops, stacks, vents, monitors and similar applications |
Coverage & How Much You Need:
Coverage per 3-gallon unit is not stated in the available sources; estimate quantity from the flashing area and fabric reinforcement schedule.
Fit and Compatibility:
Pairs with fiberglass or polyester reinforcement fabrics and roll roofing for permanent flashing repairs on roof assemblies. Confirm substrate suitability before use.
Frequently Asked Questions (FAQ):
Q: What is included in one order?
A: One 3-gallon unit of RM Lucas #779 All-Weather Flashing Cement, mid-season grade, in black.
Q: Can I apply it in wet conditions?
A: Yes, #779 may be applied to wet and even underwater surfaces, which makes it useful for emergency repairs.
Q: Does it need reinforcement fabric?
A: For permanent repairs it may be used with fiberglass, polyester fabrics or roll roofing.
Q: How does it handle on the trowel?
A: It applies fast and smooth and breaks cleanly off the trowel without stringing.
Q: Where can it be used?
A: At parapet walls, gravel stops, stacks, vents, monitors and similar flashing applications.
Q: How much flashing does 3 gallons cover?
A: Coverage is not stated in the sources, so plan quantities from the repair area and fabric schedule.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
An all-weather flashing cement like #779 earns its place in every service truck because it bonds and cures on damp surfaces where standard cements fail. Embed fiberglass or polyester membrane into the wet mastic for a permanent repair rather than relying on mastic alone. The mid-season grade is the right choice for moderate temperature application windows; adjust grade selection to your job conditions.
Contains petroleum solvents; follow label directions, ensure ventilation and keep away from ignition sources during application.
Add RM Lucas #779 All-Weather Flashing Cement to your next flashing repair order.
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