Chimney Repointing in Liverpool

What does chimney repointing involve?

Mortar is meant to be the weaker, sacrificial part of a wall. Over decades on an exposed chimney, rain, frost and wind wash it out of the joints until they are recessed, hollow or open. Water then sits in the joints and soaks into the bricks, and in winter it freezes and expands, breaking up both mortar and brick faces. Repointing replaces that worn mortar before the damage spreads into the bricks and the core of the stack.

On a chimney, repointing is rarely done in isolation. Because the stack is already scaffolded, it makes sense to check the flaunching, pots and flashings at the same time. We price these separately so you can see what is essential and what is preventative. It is one of the most common jobs we carry out as part of our chimney repairs across Merseyside.

Signs your chimney needs repointing

• Recessed jointsMortar sitting well back from the brick face, so the joints look like dark grooves from the ground.
• Mortar in the gutterSand and grit collecting in gutters, on the roof slope or on the ground below the stack.
• Plants and mossWeeds or moss growing out of joints show they are holding water.
• Spalled bricksBrick faces flaking or blown off, often after frost, exposing the soft inside of the brick.
• Damp insideDamp on the chimney breast that worsens after driving rain, with no obvious flashing problem.
• StainingDark, wet-looking patches on the stack that stay damp long after the rest of the roof has dried.

How we repoint a chimney stack

1. Inspection and photos. We look at the stack from the ground, ladder, roof or by drone and photograph the joints, bricks, flaunching and lead so you can see their condition.
2. Access. Scaffold or a powered access platform is arranged so we can reach every face of the stack safely.
3. Raking out. Failed mortar is raked out to a consistent depth, carefully so the brick edges are not damaged. Loose and hollow mortar comes out; sound mortar is assessed rather than removed for the sake of it.
4. Brick replacement. Spalled or cracked bricks are cut out and replaced with a matching or close-matching brick.
5. Repointing. Joints are dampened and filled with a mortar chosen to suit the brick, packed in firmly and finished to a profile that throws water off the face.
6. Top of the stack. We check the flaunching and pots and, if agreed, renew or repair them while access is in place.
7. Finished photos. You get photos of the completed stack before the access comes down.

Choosing the right mortar

Matching the mortar matters more than most people realise. Many older Liverpool chimneys were built with soft bricks and lime-based mortar. Lime mortar is more flexible and more breathable than modern cement mortar, which lets moisture escape through the joints rather than through the bricks. If a hard, dense cement mortar is used on soft old brick, the water and salts are forced out through the brick faces instead, and the bricks can spall even faster than before.

In general terms, older, softer brickwork tends to suit a lime-based or weaker mix, while later, harder bricks can take a mix with more cement. We look at the brick, the existing mortar and the exposure of the stack and explain what we recommend and why. We also aim to match the colour and texture of the existing joints, so the repointed stack does not stand out against the rest of the house or the neighbour’s half of a shared chimney.

Repointing or rebuilding?

Repointing is right when the stack is straight, the bricks are mostly sound and the problem is worn mortar. If the stack is leaning, has deep cracks running through it, has lots of badly spalled bricks, or the mortar in the core has turned to sand, repointing the surface will not make it safe. In that case a partial or full chimney rebuild may be needed. We will show you the evidence either way.

Chimney repointing in Liverpool and Merseyside

Many terraced streets in Walton, Everton and Bootle have stacks that have not been repointed for a very long time, and the original soft brick and lime mortar is often heavily weathered on the side facing the prevailing wind. Inter-war semis in Old Swan, West Derby and Huyton usually have shared central stacks built with harder brick, where earlier patch repairs in mismatched mortar are common. Near the coast, in Waterloo, Crosby and Birkenhead, salt-laden wind and rain tend to wear joints faster.

When we carry out chimney work around Liverpool on a shared stack, we point out that the joints on your neighbour’s side face the same weather as yours. It is often worth agreeing to repoint the whole stack at once, so scaffolding is only needed once.

What affects the cost of chimney repointing?

Access is usually the biggest single factor, followed by the size and height of the stack, how many faces need repointing, how many bricks need replacing and whether flaunching or lead work is being done at the same time. A small stack on a bungalow is very different from a tall villa stack with several pots. See our guide to chimney repair costs for how each factor works.

When should you call?

Call when you can see recessed joints or mortar in the gutters, before frost starts breaking up the bricks. If damp is already showing inside, we will check the flashings too, as a chimney leak often has more than one cause.