Chimney Repairs

Chimney Repairs Explained

Reviewed by Martin, Select Roofing Services — Family roofers in Formby, Merseyside — 30+ years on the tools · Last updated August 2026

Repointing in progress — renewing the mortar joints that hold the stack together.

A chimney stack stands higher than the rest of the roof, gets hit by weather from every direction, and is built from masonry that was never designed to last forever. It's also one of the most common sources of a genuine roof leak, and one of the easiest parts of the roof to neglect because most of it is out of sight. This guide covers what actually goes wrong, what the different repairs involve, and how to tell chimney repair from a chimney sweep — a mix-up that costs people time and money more often than you'd think.

Types of chimney repair

Warning signs to watch for

• Crumbling or cracked mortar joints — the first and most common sign, usually visible from the ground with binoculars
• Water stains on ceilings or walls near the chimney breast, or a musty, damp smell in the room
• Spalling brick — chipped, flaking or crumbling brick faces, usually from trapped moisture freezing and expanding
• A leaning or visibly tilting stack — a genuine safety concern that needs attention immediately, not a wait-and-see item
• Debris in the gutter below the chimney — mortar dust or small brick fragments often collect here before damage is obvious from the ground

Chimney repair vs chimney sweep

These two get confused constantly, and they're genuinely different trades. A chimney sweep cleans the flue — clearing soot and creosote buildup for fire safety, typically an annual job if you use an open fire or wood burner. A chimney repair addresses the structure itself: the brickwork, mortar, flashing and stack. One is fire safety and flue maintenance; the other is roofing and masonry work. Many chimneys genuinely need both, just not from the same person or on the same schedule.

Our process

Every chimney job starts with a proper look, not a guess from the ground. We assess the full stack — mortar condition, flaunching, flashing, and any signs of movement — before recommending anything. You get a clear written quote, matched materials wherever the property calls for it, and a 10-year written guarantee on the finished work. Where the job requires Building Control notification, we handle that as standard.

Why chimney work needs genuine care

A chimney stack is a narrow, isolated working platform at the highest point of the roof — there's less to stand on and further to fall than almost anywhere else on the job. Structural assessment matters as much as the repair itself: a leaning stack can be a sign of deeper movement in the stack's foundation or the roof structure beneath it, not just surface-level mortar failure. This is exactly why a proper inspection before quoting matters more on chimney work than almost any other roofing job.

Matching materials

We match brick and mortar to your existing chimney wherever possible, particularly on period properties where a mismatched repointing job is both visually obvious and can genuinely affect how the chimney weathers afterward — the wrong mortar mix can trap moisture in older, softer brick rather than letting it breathe, accelerating exactly the damage you were trying to fix.

Shared chimneys & party walls

Shared chimney stacks on semi-detached and terraced properties — common across Merseyside's Victorian and Edwardian housing stock — can fall under the Party Wall Act depending on the work involved. See our guide to party wall notices and roof work for what that means in practice before work starts.

Chimneys, pots & wildlife

An open or damaged chimney pot is an open invitation to birds and other wildlife, and older properties with slate roofs sometimes have bat roosts that carry their own legal protections. See our guides to chimney pots, cowls & wildlife and bats and re-roofing if either applies to your property.

Chimney repairs, area by area

We carry out chimney repairs across the whole of Merseyside and West Lancashire, with the same inspection-first process and 10-year guarantee described on this page.

Frequently Asked Questions

Summary

A chimney is the hardest-working, least-inspected part of most roofs. Knowing the warning signs, understanding what repointing, flaunching and flashing repair actually involve, and knowing when you need a roofer rather than a chimney sweep all help you get the right fix at the right time — before a surface crack becomes a structural problem.

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