A chimney stack is exposed on four sides, sits at the highest and windiest point of the building, and is joined to the roof by a lead detail that has to flex through every temperature swing. In central Scotland that is a punishing job, and stacks fail long before anyone looks at them.
Typical Scottish costs
- Repointing a domestic stack: roughly £400–£1,100, driven mainly by access and scaffold.
- Renewing the flaunching (the mortar cap around the pots): roughly £250–£600.
- Replacing lead flashing and soakers around the stack: roughly £350–£900.
- Partial rebuild above roof line: roughly £1,200–£3,000.
- Full removal and making good: roughly £900–£2,500.
Scaffold or tower hire is frequently a third or more of a chimney job. Combining repointing, flaunching and flashing work into one visit is nearly always cheaper than doing them a year apart.
Warning signs
- Mortar crumbs in the gutter directly below the stack, or on the ground beneath it.
- Visible gaps or recessed joints between bricks — mortar should sit close to flush.
- Cracked or missing flaunching around the pots, or a pot sitting off-square.
- Damp staining on the chimney breast in an upstairs room or the loft, especially after wind-driven rain.
- Vegetation growing from the stack, which means the joints are holding water.
Why chimneys cause damp people blame on something else
Water entering through porous mortar or a failed flashing travels down the flue or between the leaves of the brickwork and appears on a ceiling several metres from the stack. Homeowners often chase the ceiling stain, repaint it twice, and only find the cause when someone photographs the stack properly.
Inspect before you scaffold
A drone can circle a stack at close range and photograph all four faces, the flaunching and the flashings in minutes, with no scaffold and no roof access. You get every defect circled and graded, which means you can decide between repoint, rebuild and removal before hiring anyone. £99 residential, £149 commercial across Glasgow, Lanarkshire and Edinburgh.