If you are having leadwork done in Necton, knowing what each stage of the job involves helps you judge whether it is being done properly.
Leadwork is one of the roofing jobs where shortcuts are easiest to take and hardest to spot from the ground afterwards. A flashing can look neat and new from street level while being under-specified, poorly fixed, or inadequately sealed behind. Understanding what a proper job involves from first inspection through to completion means you are in a much better position to ask the right questions and spot when corners are being cut.
Below is a plain account of what correct leadwork - a chimney re-flashing, for example, which is the most involved type of domestic leadwork job - looks like at each stage.
Before any work is quoted or started, someone needs to get eyes on the problem properly. A look from the ground with binoculars is useful for an initial assessment, but it is not enough to plan a leadwork repair. The roofer needs to get onto the roof to see the existing flashings up close.
At this stage, the inspection should cover:
A proper inspection at this stage avoids the situation where the flashings are replaced and water continues to come in, because the underlying brickwork issue was not spotted or addressed.
Once the scope of work is agreed, the first job on the day is stripping out the existing lead and clearing the mortar chase. Old lead is carefully removed - it is a recyclable material with scrap value, and a responsible contractor will account for it. Any old sealant, mastic or tape residue is cleaned off the brickwork.
The mortar chase is then raked out to a depth of at least 25mm. This is the slot in the horizontal joint between bricks into which the top edge of the new flashing will be tucked. If the chase has crumbled wider than it should be, or if the brickwork around it is damaged, that needs to be made good before the new lead goes in - otherwise the new flashing will not sit tightly.
On a chimney, stripping out typically reveals the full picture for the first time. Once everything is bare, it is often possible to see rot in nearby timbers or areas where water has been travelling that were not obvious before.
Lead for chimney flashings is not a single piece - it is made up of several separate sections, each with a specific role. A typical chimney has:
Each piece is cut on site from lead sheet at the correct code thickness - typically code 4 (1.80mm) for step flashings and aprons, code 5 (2.24mm) for back gutters and wide valley applications. The sections are cut to the correct width and length, with each piece sized so that no single section is longer than 1.5 metres. This is not an arbitrary rule: longer sections cannot accommodate thermal movement properly and will split or pull away from the chase over time.
Dressing is the process of forming the flat cut lead into the correct three-dimensional shape so that it follows the roof surface and brickwork tightly. It is done with a bossing mallet and dresser - traditional tools that work the lead without thinning it or cracking it. Machine-cut or pre-formed lead can be used for simple straight runs, but complex shapes around chimney corners require hand dressing.
Each section of lead is fixed into the mortar chase using lead wedges tapped into the joint at regular intervals - typically every 450mm. These hold the flashing firmly without preventing it from moving with temperature changes. The lead is then pressed tightly to the brickwork face below the chase.
Soakers at the chimney sides are fitted as the step flashings are worked up from the bottom. Each soaker sits on top of the tile below it and under the tile above, with the step flashing lapping over it by a minimum of 65mm. This overlapping arrangement means that even if one joint allows a small amount of water in, it cannot travel further down.
Copper clips or tacks, rather than nails alone, are used to secure lead to the roof surface where it needs to be held down without being fixed so rigidly that it cannot move.
Once all sections are correctly positioned and fixed, the mortar chases are re-pointed. The mortar mix matters: it should be a relatively soft mix compatible with the existing brickwork rather than a hard modern cement mix, which can crack away from older bricks as the building moves. The pointing is finished flush or slightly recessed, not built up in a wedge shape over the top of the lead - a wedge of mortar over the lead traps water and accelerates failure.
Any chimney repointing or brickwork repairs identified at the inspection stage are carried out at this point too, before the scaffold or ladders come down.
Once the mortar has been applied, a final check covers the full installation: all laps and overlaps, the depth and integrity of the pointing, and the condition of the tiles around the base of the flashings. Any tile that was disturbed during the work is re-bedded or replaced if needed.
Offcuts and stripped-out old lead are removed from the roof and the surrounding area is cleared. A good job leaves the roof and the garden below it tidy.
Before any lead work begins on your property in Necton, it is reasonable to ask the following:
A contractor who can answer these questions clearly and without hesitation is likely to do the job properly. Dereham Roofers carry out leadwork across Necton and the surrounding area. Call us to arrange an inspection and we will talk you through exactly what your job involves before anything is agreed.
No obligation · We usually respond within 2 hours
Storm damage, active leak, damaged ridge - we aim to be on-site within 24 hours.
