Chimney Leak Repair: Protect Your Chimney from Water Damage

Moisture infiltration weakens mortar joints, causes brick spalling, and accelerates freeze-thaw damage in cold climates. Left untreated, a simple leak can lead to costly masonry restoration or even a full chimney rebuild.

Persistent leaks also encourage mold and mildew growth in attic or wall cavities. Compromised flashing, cracked crowns, and failing mortar allow water to penetrate interior structures, leading to hidden damage and health risks.

By addressing leaks promptly with professional chimney leak repair, you safeguard your home’s structural integrity, maintain heating efficiency, and prevent small issues from escalating into major repairs.

• Cracked Chimney Crown: Water pools on a deteriorated crown and seeps into masonry.
• Failed Flashing: Rusted or improperly installed flashing between roof and chimney allows water entry.
• Damaged Mortar Joints: Eroded or missing mortar (repointing needed) permits moisture penetration.
• Faulty Chimney Cap: Missing or damaged caps let rain and debris into the flue.
• Brick Spalling & Cracks: Deteriorated brick faces enable water to infiltrate the inner chimney structure.

1. Comprehensive Inspection: A certified technician conducts a thorough chimney survey—examining the crown, flashing, mortar joints, and brick faces—to pinpoint all leak sources.

2. Repair or Replace Chimney Crown: If the crown has cracks or spalling, the old crown is removed, and a new, properly sloped crown is poured or installed to shed water away from the chimney stack.

3. Flashing Replacement & Sealing: Damaged or rusted flashing is replaced with new stainless steel or copper flashing. High-grade roofing sealant is applied around all seams to create a waterproof barrier.

4. Tuckpointing Mortar Joints: Deteriorated mortar between bricks is removed and repointed with new masonry mortar to restore a tight seal and prevent water intrusion.

5. Brick Repair & Spalling Treatment: Spalled or cracked bricks are replaced or patched with color-matched masonry compound. Brick faces are sealed with a breathable waterproofing agent to repel moisture while allowing vapor to escape.

6. Chimney Cap Installation: A new stainless steel chimney cap with mesh screen is installed to keep rain and debris out of the flue, further preventing future leaks.

Long-Lasting Waterproofing: Certified technicians use high-quality sealants and mortar that flex with temperature changes, ensuring durable protection against moisture.

Prevent Costly Masonry Damage: Early leak repair saves on extensive masonry restoration or chimney rebuild costs by preventing widespread deterioration.

Enhanced Energy Efficiency: Properly sealed chimneys prevent drafts and heat loss, keeping your home warmer and reducing energy bills.

Peace of Mind & Compliance: Professional repairs comply with local building codes and insurance requirements, providing documentation that your chimney is leak-free and safe.

How do I know if my chimney is leaking?

Look for water stains on the ceiling or walls near the chimney, mortar joints crumbling, efflorescence (white salt deposits) on bricks, or rust on flashing. A professional inspection can confirm leak sources.

Can I apply waterproofing sealant myself?

While DIY sealants can temporarily repel moisture, only professionals ensure proper surface preparation, correct product selection, and complete coverage—especially on damaged crowns or flashing.

How much does chimney leak repair cost?

Costs vary by region and extent of damage. Simple flashing replacements start around $300–$500. Extensive crown rebuilding, tuckpointing, and brick repairs can range from $800–$2,000. Always request a written estimate.

How often should I inspect my chimney for leaks?

Inspect your chimney annually—preferably before the rainy or freezing season. Check for visible cracks, spalling bricks, and deteriorated mortar joints to catch leaks early.