If your chimney, dormer or valley is letting water in around Hellesdon, failing leadwork is the most likely cause - and choosing the right roofer to fix it properly makes all the difference.
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Lead is the material of choice for sealing the joints where a roof meets a vertical surface - around chimneys, at the base of dormers, along roof valleys, and at parapet walls. When it is cut, dressed and fixed correctly, it outlasts almost every other roofing material. When it is bodged or allowed to deteriorate, it becomes the most reliable route for water into your home.
A persistent damp patch on a chimney breast wall, a wet ceiling below a dormer, or staining along a valley line almost always points to a leadwork failure rather than a broken tile. The tile gets the blame, but the lead is usually the problem. Understanding that saves you money: a small lead repair costs a fraction of what replastering and redecorating a wet ceiling will cost once the water has been getting in for a season.
Good leadwork is a craft, not a patch-and-go job. Lead sheet comes in different codes - Code 3 through to Code 8 - with higher code numbers indicating greater thickness and weight. The right code for each location depends on the detail being formed. Chimney flashings typically use Code 4 or Code 5 lead. Valley linings often call for Code 5 or Code 6. A roofer who uses Code 3 everywhere is cutting costs at your expense.
The lead is cut to shape on the ground and then dressed - formed by hand or with a dresser tool - to fit tightly against the surface it is sealing. Where a flashing meets a brick or stone joint, it is tucked into a raked-out mortar joint (called a chase) and wedged in place with lead wedges before the joint is pointed with mortar or leadmate. This mechanical fixing is what holds it long-term; relying on sealant alone is a warning sign.
Long runs of lead must be laid in sections no more than around 1.5 metres, with lapped joints between each piece. Lead expands and contracts with temperature changes. If a flashing is installed in one long piece, it will buckle, crack at fixing points, or pull away from the chase - all of which let water in. Correct sectioning is one of the details that separates a proper job from one that looks fine in November and leaks by March.
Leadwork fails for several reasons, some due to age and some due to poor installation. Knowing which you are dealing with affects the repair approach.
Leadwork is a skill that takes time to learn properly, and it is not uncommon for general builders or unskilled labourers to attempt chimney flashings with limited understanding of how lead behaves. The result is often a roof that passes a visual inspection but leaks within a year. Before you agree to any leadwork quote, ask these questions directly.
A contractor who knows their trade will answer this without hesitation and will be able to explain why they have specified a particular code for each element of the job. If the answer is vague, or if they simply say "good quality lead", ask for the code number in writing. Code 4 or 5 for chimney flashings and Code 5 or 6 for valleys is the standard range for most residential work. Code 3 is too thin for most exposed positions.
The correct answer involves raking out the joint to a depth of around 25 mm, inserting the lead into the chase, and wedging it with lead wedges before pointing with mortar or a specialist sealant such as leadmate. If the contractor says they will use silicone or frame sealant to bond the lead to the brickwork surface only, that is not a correct installation. It may hold for a season or two but it will not last.
Sections should be no longer than approximately 1.5 metres (150 mm for step flashings). If the contractor proposes running a single piece of lead across a full chimney width of, say, 900 mm to 1,200 mm as one unbroken piece, that may be acceptable for small details - but for longer runs you want to hear about lapped joints and the reasons for sectioning. A contractor who does not mention thermal movement at all has probably not thought about it.
Photographs of finished work on similar roof types are a reasonable request. You are looking for clean lines, tight dressing to the surface, and visible lead wedges in the chase. Bulging, uneven or wrinkled flashings in the photos suggest the lead was not worked properly. If the contractor has no photos, that is not automatically a problem, but it does mean you are taking more on trust.
Leadwork repairs often involve more than just the lead itself. Re-pointing the mortar chase after the new flashing is installed should be included. If chimney brickwork is damaged or if pointing elsewhere on the stack needs attention, that should be identified and quoted for separately before work starts - not flagged as an extra once the scaffold is up. Ask specifically whether the quote includes chase raking, lead wedges, pointing and clearing away of the old material.
For most chimney and dormer work, scaffold or a scaffold tower is the only safe means of access. A roofer who proposes to do the work from a ladder for a chimney stack repair is cutting corners on safety and almost certainly on quality too. Ask what access equipment will be used and whether the cost is included in the quote. If a scaffold is going up, it is worth getting other minor roof repairs done at the same time to make the most of the access.
A water test - running a hose slowly over the completed area - is the proper way to check that a flashing is watertight before the job is signed off. Not every contractor does this as a matter of course, but it is worth asking. At minimum, you want confirmation that the dressed lead is sitting flush against all surfaces, that the chase is fully pointed with no gaps, and that any felt or underlayer below has been checked for damage while the area was open.
Some roofing firms subcontract leadwork to a specialist. That is not necessarily a problem, but you should know who will actually be on your roof. Ask who carries out the lead work and whether the person doing it has done similar jobs before. If the firm is subcontracting, ask whether the subcontractor is covered by any form of professional indemnity and whether you will have a direct point of contact with them.
Any reputable contractor should provide a written quote before work begins. The quote should specify the location of the work (chimney rear gutter, left-hand valley, dormer cheek, and so on), the lead code to be used, the method of fixings, and whether pointing and clearing are included in the price. A quote that simply says "renew flashings" with a price gives you very little to hold the contractor to if the work is not done correctly.
If the quote is verbal, ask for it in writing by email at minimum. This is not about distrust - it is simply good practice for any building work, and a contractor confident in their own work will have no objection to it.
Leadwork prices vary depending on the scale of the job, the access required and the lead code specified. As a general guide for residential property in this part of Norfolk:
These figures assume scaffold or tower access is either already in place or added separately. A scaffold for a single-storey extension chimney typically adds £150 to £300; a full-height scaffold for a two-storey chimney stack can add £400 to £700. Always ask whether scaffold is in the price before comparing quotes.
Lead has been used in roofing for centuries because it is durable, easily worked, and can be formed to any shape. In new-build work, aluminium or zinc flashings are sometimes specified instead, and proprietary systems using reinforced membranes are used on some lower-specification buildings. For repairs to existing residential roofs - especially period properties - lead is almost always the correct choice because it matches the existing material, is accepted by planning authorities for listed buildings, and will outlast alternatives when correctly installed.
Aluminium flashings are cheaper but can react with certain mortar types and are harder to dress tightly around complex profiles. They suit straightforward modern details but are not ideal for older brickwork or irregular surfaces. If a contractor proposes aluminium as a like-for-like replacement for lead, ask why and whether it will be accepted if the property is listed or in a conservation area.
Small areas of lifted or cracked lead can often be repaired if the underlying metal is still sound and in the correct code weight. A repair is appropriate when the lead is less than 30 to 40 years old, has no pervasive cracking, and has simply pulled away from its fixing point. A lead repair patch welded or soldered into place by someone who knows what they are doing can extend the life of a flashing by another decade or more.
Replacement is the right call when the lead shows widespread surface cracking, is visibly corroded through, is in too thin a code, or when previous sealant repairs have been applied over and over and the lead underneath is no longer sound. Replacing old lead with correctly specified new lead is a worthwhile investment: well-fitted Code 4 or 5 lead flashings should last 50 to 80 years before needing attention again.
Every leadwork job starts with a proper look at what is actually failing - not just what is visible from the ground. We cut and dress lead to the correct profiles for the detail being formed, fix into raked mortar chases with lead wedges, and point up properly before leaving. We do not use sealant as a substitute for correct installation.
If you have a persistent leak around a chimney, dormer or valley that has not been resolved by previous repairs, it is worth having a roofer survey the roof. We will tell you honestly what is causing the problem and what it will take to fix it properly.
Before you pick up the phone, it helps to have a few things ready. Where exactly is the damp appearing inside? How long has it been happening? Has anyone worked on the roof recently? Is the leak linked to particular weather conditions - heavy rain, wind-driven rain from a specific direction, or frost? The answers help a roofer identify the most likely cause quickly and give you a more accurate quote.
If you can safely see the leadwork from a window or from the ground with binoculars, look for obvious signs: lead that is standing proud of the brickwork, white staining (lime bloom from failed mortar pointing), or visible cracking and wrinkling on the lead surface. These observations are worth mentioning when you call.
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