Chimney Flashing & Roof Leak Repair

Leaks at the Chimney Base—Why They Happen

The most common roof leak we fix on Long Island starts where the chimney flashing meets shingles. Flashing is a two-part system: step flashing tucks under each shingle course, and counter flashing overlaps and protects the step pieces, turning water out and over the roof. When step pieces are missing, the counter flashing is just a glued-on strip, or the joint sealants have aged out, water tracks into the attic or ceilings. Wind-driven rain from Nor’easters makes marginal details fail fast. The right repair requires properly layered metal that sheds water by gravity—not caulk alone.

Our Flashing Repair & Replacement Process

1. Inspect & trace the leak: We look for water paths in the attic, check decking condition, examine shingle integration, and evaluate existing metal.
2. Step flashing reset: We replace missing or corroded step pieces and weave them with shingles as the manufacturer intends—no shortcuts.
3. Reglet-cut counter flashing: We grind clean joints in the masonry and insert new metal counter flashing, locking it into the mortar for a watertight, long-term seal.
4. Cricket (saddle) if needed: On wide stacks or steep pitches, we build a small rooflet behind the chimney to split runoff and prevent pileups of snow, leaves, and debris.
5. Sealants & finishes: We use compatible, UV-stable sealants as backup—not the primary waterproofing—and color-match where appropriate.
6. Water test: When requested and safe, we conduct controlled flow testing to verify performance without flooding the roof.

Signs Your Flashing Is Failing

• Ceiling stains or peeling paint near the chimney chase
• Wet attic insulation or damp rafters after storms
• Rust trails on flashing or counter metal lifting from the brick
• Sealant beads cracked or missing, or smeared “patches” over gaps
• Shingles cut short or tarred over at chimney edges

If you see any of these, don’t wait—small flashing issues become decking rot quickly. We’ll show photos of what we find and explain the cleanest fix so you can make a confident decision.

Materials That Stand Up to Coastal Weather

We primarily install galvanized or stainless steel step and counter flashing depending on exposure and budget; copper is available for premium or historic applications. On crickets, we build solid framing and deck it with appropriate underlayment before flashing. We avoid dissimilar-metal contact that can accelerate corrosion in salt air.

Why “Tar It” Isn’t a Real Fix

Roofing cement and generic caulk dry out and crack, especially in sun and wind. Slathering more goop over failed flashing looks sealed today but leaks again the next storm. Lasting repairs require properly lapped step flashing under shingles and reglet-set counter flashing in the masonry so water is guided out by design.

Pair This Repair With

• Chimney caps to stop wind-driven rain and debris from entering the flue.
• Crown repair if cracks at the top are contributing to water entry.
• Masonry waterproofing to reduce absorption in the upper courses and shed storms more effectively.
• Inspections to document conditions and plan preventative maintenance.
• Masonry repair if mortar joints around the flashing are deteriorated.