Chimney maintenance: what to do and when to call a roofer

Chimneys cause more roof leaks than anything else. Most are fixable without rebuilding the stack.

What to check annually

• Flashing — the lead where the chimney meets the roof. Look for cracks, lifting, or missing pieces.
• Pointing — the mortar between bricks. Crumbling mortar lets water in.
• Pots and cowls — the chimney pot and any cowl. Missing or loose pots are common.
• Bricks — spalling (flaking) bricks indicate water damage, often from failed flashing above.
• Lean — any visible lean means the stack needs rebuilding. Safety issue.

What you can DIY

Visual inspection from ground level. Binoculars help. Check pointing by tapping with a wooden handle — solid pointing rings true, hollow pointing sounds different.

What's a professional job

Flashing replacement, repointing, brick replacement, stack rebuilding. These need working at height and lead-working skills.

Common issues and their cost

• Re-flashing around chimney (lead work): £300-£600
• Repointing: £150-£400
• Cowl installation: £100-£200
• Partial rebuild (top courses): £500-£1,500
• Full chimney rebuild: £2,000-£4,000

When to act fast

Active water staining on the chimney breast or ceiling near the chimney. That means flashing has failed and water is getting in. Don't wait — call a roofer.

We repair and rebuild chimneys across Wimbledon and South London. Honest assessment, no upsell.