North Walsham Roofers carries out lead flashing and weathering work in Sheringham and across Norfolk, handling every stage of the job from first inspection through to final clean-up.
Lead flashing keeps water out at the points on your roof where two different surfaces meet: around chimney stacks, along dormer cheeks, above skylights, and in the valleys between roof slopes. When the lead is failing or was never installed correctly, water finds those junctions and works its way into the building. Getting it fixed properly means doing the job in the right sequence, with the right materials, and not cutting corners at any stage.
Below is a plain account of what a lead work job involves from start to finish, so you know what to expect and what questions to ask before any roofer starts work on your property in Sheringham or the surrounding area.
Before any lead is cut or any old material is removed, the first job is to understand exactly what is happening. A proper inspection looks at the lead flashing itself, the masonry or substrate it is fixed to, the tiles or slates around it, and any evidence of where water has entered.
On a chimney, that means checking the front apron, the stepped soakers and cover flashing on each side, and the back gutter behind the stack. On a dormer, it means checking the cheek flashings, the head flashing above the window frame, and the valley junctions where the dormer roof meets the main slope. Each element can fail independently, so inspection needs to be thorough rather than stopping at the most obvious visible problem.
It is also worth checking the condition of the pointing in the mortar chase - the groove cut into the brickwork that holds the top edge of the flashing. Failed pointing is a separate problem from failed lead, and both need to be addressed. Replacing the lead without re-pointing the chase is an incomplete job.
Not every lead flashing problem requires full replacement. A decision needs to be made about each section of lead based on its condition, its age, and whether it is the right Code (thickness) for the application.
Lead that has cracked along fold lines due to thermal fatigue, lead that has corroded through, or lead that was installed in pieces that are too long and have buckled, generally needs replacing. Lead that has simply lifted at the top edge because the mortar pointing has failed can sometimes be re-fixed and re-pointed without cutting new material. The distinction matters because it affects both the cost and the scope of work.
Where a previous repair has been made with mastic sealant or adhesive flashing tape, that material needs to come off entirely before any assessment of the lead beneath it is possible. Mastic hides the underlying condition and does not constitute a repair - it is a stop-gap.
Lead work on chimneys and dormers requires safe working at height. Depending on the height of the stack and the pitch of the roof, this means scaffolding, a tower, or crawl boards - the right choice depends on the specific job. Scaffold is often needed for chimney work because both hands need to be free to cut, dress, and fix the lead, and because the work may take more than a few hours.
Before any work starts, the working area around the base of the scaffold or ladder should be cleared. Tiles, lead offcuts, and old mortar will come off the roof during the job, and the area below needs to be managed accordingly.
Old lead is taken off carefully. If soakers are being replaced, the tiles or slates around them need to be lifted and set aside so the soakers can be removed from beneath them. Lead in a valley is lifted from the bottom upwards, working back up the slope. Chase-fixed flashings are raked out of the mortar joint before the lead is pulled free.
The old lead is retained - it is a recyclable material with real scrap value, and it is worth asking whether a roofer intends to take it with them or whether they leave it. The scrap value is generally reflected in the overall job cost.
Once the old lead is off, the substrate is inspected. Timber rolls or drips in a valley may need replacing. Brickwork around the chase may need cutting back if the groove is too shallow. Any tiles or slates that were cracked or damaged during removal need to be flagged up at this stage.
New lead is cut on site to the dimensions required. The Code (thickness) of the sheet is selected for the specific location - Code 4 or Code 5 is typical for chimney aprons and cover flashings, Code 5 for back gutters and valley linings. Each piece is cut to a length that allows for thermal movement without buckling, which for Code 4 in an abutment flashing means individual pieces no longer than 1.5 metres.
Dressing the lead is the skilled part of the job. Lead is soft and responds to a bossing mallet or dressing tool, and it needs to be worked into internal and external corners without splitting or thinning. A corner that has been forced rather than properly dressed will crack in time. Good lead work is tight, clean, and follows the shape of the surface without gaps or visible stress marks.
Soakers for a tiled or slated abutment are cut individually to match the gauge of the slate or tile course. Each soaker slips under the overlapping tile above and sits against the wall surface. The cover flashing then overlaps the upstand of the soaker by at least 65 mm, so that any water running down the wall cannot get between the two layers.
The top edge of a cover flashing is fixed into the mortar chase with lead wedges tapped in at intervals - this is the correct method, not a bead of sealant along the top edge. The wedges compress the lead firmly in the groove and allow a small degree of movement without loosening.
The chase is then pointed with mortar. The mix needs to be appropriate for the masonry - a hard cement mix in an old lime-mortared chimney will cause the brickwork to crack as the stack moves. Pointing should be finished flush with the face of the brickwork, not proud, and the joint should be fully filled with no voids that could hold water.
Where lead clips are used to restrain the bottom edge of a flashing on a long run, they are spaced to allow thermal movement while preventing the lead from lifting in high winds.
Any tiles or slates lifted to allow access to soakers are replaced and checked for correct seating and bond. Broken tiles identified during the job are replaced rather than put back. Once tiles are back in place, the whole area is checked from above to confirm all laps are correct, no tile is sitting proud, and there are no exposed nail heads or open joints.
A final visual check from below confirms the pointing is complete, the lead edges are dressed down, and the scaffold or access equipment has not damaged any gutters, fascias, or tiles during the job.
All old lead, mortar debris, broken tile fragments, and general waste are cleared from the roof and from the working area at ground level. The old lead is removed for recycling. The site should be left clean - there should be nothing left on the roof, in gutters, or on paths and gardens below.
We carry out lead flashing and weathering work across Sheringham and throughout Norfolk from our base in North Walsham. We also cover nearby towns and villages across the wider area. If you have a lead flashing problem or want a survey carried out before a problem develops, call us to arrange an inspection.
No obligation · We usually respond within 2 hours
Storm damage, active leak, damaged ridge - we aim to be on-site within 24 hours.
