MasonryDefender Chimney Crown Sealer – Brushable Elastomeric Waterproof Sealant (1/2 Gallon)

The MasonryDefender Chimney Crown Sealer is a brushable elastomeric waterproof sealant designed to guard masonry or concrete chimney crowns from water intrusion and surface imperfections. Its flexible film moves with temperature shifts and crown movement, providing a protective barrier that helps seal out dampness and supports the crown through varied weather conditions. This coating is built to adapt and remain durable over time, helping homeowners maintain a neat, protected exterior around the chimney.

What it is and how it works

At its core, the sealant forms a flexible waterproof membrane that adapts to the crown surface. It’s engineered to stop water leaks quickly and to resist chipping or cracking over time, even when exposed to outdoor weather. The formula remains pliable after curing, so minor crown movements don’t easily compromise the seal.

Key benefits

• Elastomeric waterproofing sealant forms a flexible membrane that protects masonry crowns from water intrusion and dampness.
• Flexible repair material addresses minor cracks and crown imperfections without cracking or flaking over time.
• Brushable formula requires no primers or pre-coats, simplifying the repair process and saving time.
• Two-coat application delivers durable waterproofing while maintaining surface flexibility.
• Surface prep tips emphasize cleaning, drying, and masking to maximize adhesion and a clean finish.

How to apply

• Prep the crown: ensure it is clean, dry, and structurally sound; remove debris with a stiff brush; cover surrounding areas with drop cloths.
• Apply the first coat with even brush strokes, then proceed with a second coat for best waterproofing.
• Allow the coating to dry sufficiently between coats; expect touch dry in 30–60 minutes and full cure in 2–4 hours, depending on conditions.
• After curing, inspect for even coverage and recoat any thin spots if needed.

Coverage, timing, and practical notes

With two coats, each half-gallon covers up to about 20 square feet, though actual coverage depends on surface texture. The sealant dries quickly, enabling faster project completion and reducing weather exposure during repair work. Plan repairs for a dry window to help ensure proper adhesion and curing.

Before applying, ensure the crown is sound, and take standard safety precautions to protect the roof and surrounding area during the project. Following these guidelines helps create a reliable barrier against moisture while preserving the crown’s appearance.