Poorly fitted or failed lead flashing can cause roof leaks in homes, and lead work is best carried out to traditional standards.
Lead work covers every situation where your roof meets a vertical surface, a change of angle, or a penetration through the covering. That includes flashings where a roof slope meets a chimney or a parapet wall, valleys where two slopes meet, soakers tucked under individual slates or tiles at abutments, and flat roof coverings in lead sheet. All of these rely on hand-dressed lead cut and shaped on site to fit your specific roof, not off-the-shelf strip products.
The material itself is graded by thickness, referred to as "code". Code 3 and code 4 sheet is used for soakers and small flashings. Code 4 and code 5 is standard for chimney flashings and valleys. Code 6 and above is used where a larger area needs covering or where exposure demands extra durability. Using an underweight code is a common reason for premature failure, so it is worth asking which code will be used and why.
Lead is a long-lasting material, but it does fail over time. The most common causes are thermal movement cracking the mortar joints that hold flashings in place, original fitting with insufficient overlap or no proper step detail, and oxidation splitting older sheet that was never correctly sized. Wind uplift can also pull stepped flashings away from brickwork if the original fixings were inadequate.
A common problem is that a leak appears on the ceiling well away from where the lead is actually failing. Water tracks along rafters and battens before it finds a gap, so the wet patch inside tells you there is a problem but rarely tells you exactly where. A proper inspection from roof level - not just looking from the ground - is needed to locate the source.
The right time to act is before the water reaches your ceilings or timbers. Stained plasterwork, damp in a loft space after rain, or lifting wallpaper near a chimney breast are all signs that lead work should be checked. Leaving a minor flashing failure can allow water to saturate roof timbers, which turns a straightforward lead repair into a more costly job involving structural timber work as well.
This is the angle that matters most when you are trying to decide whether to go ahead with work. Knowing what actually happens from start to finish helps you ask the right questions and know whether the work is being done properly.
Before any work is priced or planned, the lead work needs to be seen properly. That means getting onto the roof, not just looking from a ladder at the eaves. On a chimney job, the roofer needs to see the back gutter (the lead channel behind the chimney stack), both side flashings, the apron at the front, and the condition of the mortar pointing in the raggedge chases. On a valley, the full length of the lead needs to be walked if access allows, checking for splits, lifted edges and failed clips.
At this stage a good roofer should be able to tell you whether the lead can be repaired or needs replacing, what code of sheet is appropriate, and roughly how much lead will be required. If the inspection reveals that the underlying timbers or tile courses are also damaged, that should be flagged at this stage, not discovered mid-job.
For Poringland properties, as with anywhere in this part of Norfolk, it is worth checking the condition of chimney pointing and the brickwork itself at the same time. Mortar that is crumbling will need attention before new flashing is fitted, because new lead bedded into failing joints will not hold.
Safe access matters as much as the lead work itself. For a single-storey extension or a low lean-to, a ladder and standoff is often enough. For chimney flashings on a two-storey house, a scaffold or tower is typically needed to work safely and to carry the lead sheet, clips and tools without risk. Access on a tiled or slated roof should always use roof ladders (also called cat ladders) that hook over the ridge and spread the roofer's weight without breaking tiles.
Good access also means tiles and slates around the work area can be lifted, removed and set aside properly. Tiles cracked by a roofer kneeling directly on them is a sign that access was not set up correctly. When the job is done, the same tiles go back in the same positions.
On a replacement job, the old lead comes off first. Flashings are released from their mortar chase by carefully raking out the old mortar. Soakers are lifted individually from between each slate or tile. Valley lead is removed in sections.
This stage also reveals the condition of what is underneath. Any felt or underlay beneath the valley lead, the timber tilting fillet behind a back gutter, and the condition of the roof deck or battens all become visible. Any problems found here are best dealt with before the new lead goes in, not left and covered over.
This is the skilled part of the job. Lead sheet is unrolled and cut to length, then dressed by hand using bossing tools - wooden or plastic mallets and dressers that shape the lead around angles and projections without splitting it. Flashings are folded at the back into a raggedge that sits in the mortar chase. Valleys are dressed with a central crease and turned up at the sides. Soakers are cut and bent to fit the gauge of the slates or tiles being used.
Each piece of lead must be fixed with lead clips or wedges at appropriate intervals to allow for thermal movement. Lead expands and contracts significantly with temperature changes, and if it is fixed too rigidly it will crack. This is why no piece of lead should run more than about 1.5 metres without a movement joint, and why proprietary adhesives are not a substitute for proper fixings.
On a chimney, the typical sequence is soakers first (if the roof is slated), then the step and cover flashings up the sides, then the back gutter, then the apron at the front. Each piece overlaps the one below it so water is directed outward and downward at every joint.
Once the lead is in place, the raggedge at the top of each flashing is pointed with mortar or, increasingly, with a lead-compatible mastic sealant that accommodates movement better than sand-and-cement mix. The choice depends on the application and the substrate. On older brickwork, a lime-based mortar is often more appropriate than a hard cement mix.
The pointing should be finished neatly and pressed firmly into the chase. A flashing that is only lightly tapped in or pointed with a thin skim of mortar will pull away with the first hard frost or strong wind. If a roofer cannot show you or describe how the flashings are fixed into the masonry, that is worth questioning before you agree to the work.
Before the scaffold or ladders come down, the completed lead work should be checked. Every overlap should shed water outward. Every clip or wedge should be secure. The mortar or sealant pointing should be sound. Any disturbed tiles or slates should be re-bedded or re-nailed as needed, and ridge tiles disturbed for chimney access should be re-pointed.
At this stage it is also worth checking that the gutters or valleys directly below the work are clear. Lead off-cuts, old mortar fragments and debris from the work area can block outlets and cause water to back up. A properly finished job leaves the drainage working as it should.
Old lead is scrap metal and has a salvage value. On a proper job the old lead is taken away, not left in your garden or skip for you to deal with. Any other waste - broken tiles, old mortar, packaging - should leave with the roofer. The work area should be checked at ground level too, particularly around a chimney where old mortar and lead clips can fall into borders or onto paths during the work.
Chimney flashing replacement on a standard two-storey house in this part of Norfolk typically costs in the range of £400 to £900 depending on the size of the stack, the number of flashings involved, and the access required. A valley re-lead on a standard semi can run from £350 to £700. Small soaker repairs or individual flashing patches at the lower end of that scale can cost from £150 upwards, but the cost of access often accounts for a significant share of the total.
Flat roof lead coverings are priced by area. Lead flat roofs are generally used over bay window tops, small outriggers and porch canopies. Expect to pay from around £90 to £150 per square metre for lead sheet at code 5 or 6, plus any necessary decking or substrate repairs beneath.
These are typical current figures for the Norwich area and nearby villages including Poringland. Prices vary with material costs and the condition of the substrate once the old lead is off.
A lead inspection often reveals other issues at the same time. Cracked ridge tiles, broken slates or plain tiles, missing pointing on a chimney stack - these tend to be spotted when the roofer is already on the roof and looking closely. Dealing with minor adjacent repairs at the same time as a lead job saves returning with separate access later, which reduces the overall cost. Any such findings should be shown to you or described clearly so you can decide whether to include them.
If you have a pitched roof with a slate or tile covering and have not had it checked for several years, having the lead work inspected as part of a general roof check makes sense. The lead flashings and valleys are often the first part of a roof to show signs of deterioration.
Norwich Roofers carries out lead work across Poringland and the surrounding area, including neighbouring villages and the wider south and east Norwich catchment.
If you have a flashing that has failed, a valley that leaks, or you would like the lead work on your property checked before problems develop, call us to arrange a roof survey. We will look at the lead work properly, from the roof, and give you a straight answer about what needs doing and why.
No obligation · We usually respond within 2 hours
Storm damage, active leak, damaged ridge - we aim to be on-site within 24 hours.
