Chimney Lead Flashing Repair in Liverpool

What is chimney flashing made of?

A properly flashed stack has several pieces of lead that work together. Each has a specific job, and a leak often comes from one piece failing while the rest look fine from the street.

• SoakersSmall L-shaped pieces of lead laid under each slate or tile along the sides of the stack, turning up against the brickwork.
• Step flashingLead cut in steps and tucked into the mortar joints of the stack, covering the upturns of the soakers so water cannot get behind.
• Front apronA single piece across the downhill face of the stack, dressed over the slates or tiles below.
• Back gutterA small lead gutter on the uphill side that collects water running down the roof and diverts it around the stack.
• Cement filletsA sand and cement wedge used instead of lead on some older or cheaper jobs. It works for a while but cracks as the roof moves.

Signs your chimney flashing has failed

• Lead visibly lifted, flapping, or pulled out of the brick joints.
• Splits or holes in the lead, often on old, thin or overworked sheets.
• Cracks or gaps in a cement fillet along the side of the stack.
• Silicone or bitumen smeared over the flashings, usually a sign of an earlier quick fix.
• Moss, leaves or debris piled behind the stack in the back gutter.
• Damp on the chimney breast or ceiling beside it after rain, or wet timbers around the stack in the loft.

Many of these can be seen from the ground with binoculars, or from the loft with a torch after rain. Please do not climb onto the roof.

Repair or re-lead?

Some flashing faults are local: a step that has come out of its joint can be refixed and the joint repointed, or a short split can be dealt with. If the lead is thin, brittle, heavily patched, or the back gutter has split, it usually makes more sense to strip and re-lead. As with all our Liverpool chimney repairs, where a cement fillet has cracked, we normally recommend replacing it with lead soakers and step flashing rather than patching the cement, because a new fillet will crack again for the same reason.

New lead work is cut and dressed on site to suit the stack, using lead of a suitable code (thickness) for each part, and fixed so it can expand and contract without tearing. Where lead is tucked into the brickwork, the chase is cut into the mortar joint and repointed. We avoid relying on sealants as the main defence, because they fail in sunlight and frost.

How we repair chimney flashing

1. Talk it through. We call back and ask where the damp shows, when it appears and whether the stack is shared with a neighbour.
2. Inspect. We check the flashings from the ground, ladder, roof or drone and look in the loft, then photograph what we find.
3. Quote. You receive a written quote explaining whether we recommend repair or re-leading, and any related work such as repointing.
4. Access. Scaffold or a platform is set up so the stack can be reached safely.
5. Strip and prepare. Old lead, fillets and failed sealant are removed, slates or tiles beside the stack are lifted where needed, and chases are cut.
6. Lead work. Soakers, step flashing, apron and back gutter are fitted and dressed, and the chases are pointed.
7. Make good and photograph. Slates or tiles are refitted, debris cleared, and you get photos of the completed lead work.

Flashing problems we see across Liverpool

Victorian terraces in Kensington, Toxteth and Wavertree often have stacks on the ridge shared between two houses, and over the years many have had one side re-leaded and the other patched with cement or sealant. Inter-war semis in Huyton, Prescot and St Helens commonly have shared central stacks with cement fillets that have cracked along their length. On rear chimneys that sit on the slope of the roof, back gutters fill with leaves and moss and overflow. In exposed spots such as Waterloo and New Brighton, strong winds can lift poorly fixed lead.

Whatever the house, flashing failures account for a large share of the leaks we are asked to look at as a professional chimney repair service, and they are usually straightforward to put right once access is in place.

What affects the cost of flashing repairs?

The main cost factors are access, the size of the stack, whether it sits on the ridge or the slope (a back gutter adds work), whether you need a local repair or full re-leading, and whether slates or tiles around the stack need replacing. Our chimney repair cost page explains these in more detail. If the stack is redundant and causing repeated trouble, chimney stack removal is sometimes worth comparing.

When to call

Call when you see lifted or missing lead, cracked fillets, or damp that follows rain. Flashing leaks rarely improve on their own, and water running down inside the roof can rot battens and rafters. If you are not sure whether flashing is the cause, our chimney leak repair page explains how we trace a leak.