What It Does

Flashing is the thin metal that seals the spot where your chimney meets the roof. Its job is simple but critical: keep water out. It’s usually made of aluminum, copper, or galvanized steel and tucked neatly under roof shingles. When it’s done right, you’ll never notice it. When it fails, you’ll definitely notice the leaks.

What Can Go Wrong

A few warning signs:

• Rusted or loose flashing

• Water stains on ceilings or walls near the chimney

• Peeling paint or soft spots around the chimney

• Caulk or tar patches that keep cracking

Flashing doesn’t last forever. Wind, roof movement, and temperature swings can loosen or warp it over time, creating tiny gaps that let water sneak in.

How the Pros Fix It

During an inspection, a chimney sweep will check the flashing for rust, separation, and cracks. Minor issues can often be repaired with a waterproof sealant system. If the metal itself is shot, your sweep can work with a roofer to replace it properly.

Many professionals use FlashSeal, a flexible, waterproof coating that creates a seamless barrier between the chimney and roof. It stretches, flexes, and stays watertight through years of rain, heat, and freeze cycles.

The Products They Trust

FlashSeal: A professional-grade flashing repair system that forms a durable, flexible membrane to seal leaks where the chimney meets the roof. It’s easy to apply, cures quickly, and protects against future water intrusion.