Thetford Roofers carries out lead flashing installation and repair in Bury St Edmunds, sealing chimneys, skylights, valleys and abutments to a traditional, long-lasting standard.
Lead is used wherever two surfaces meet on a roof - around chimney stacks, along parapet walls, at the junction of a roof slope with a vertical wall, in valleys where two pitches meet, and around skylights or roof windows. These are the points where water is most likely to force its way in. A roof that is otherwise in good condition can develop a serious leak if the lead at any one of these junctions fails.
Failing lead is one of the most common causes of internal water damage in homes. It rarely announces itself dramatically. More often the signs are a damp patch on a ceiling, a musty smell in a loft, or staining around a chimney breast - damage that has been building quietly for months before it becomes obvious.
When lead work needs replacing, homeowners sometimes ask whether there are alternative materials. It is worth understanding what each one does and does not offer before making a decision.
Lead is the benchmark material for roof flashings and has been used in British roofing for centuries. It is highly malleable, meaning it can be shaped and dressed into complex profiles around chimney haunches, stepped against brickwork or formed into a box gutter. It expands and contracts with temperature change, which is why it is laid in sections with small movement gaps rather than as a single run. Properly installed, lead flashings typically last 50 to 100 years before replacement is needed - though the mortar pointing that holds the top edge into the brickwork usually needs raking out and repointing every 20 to 30 years.
The main disadvantages are cost and, in some areas, the risk of theft. Lead is a commodity metal and its price fluctuates. It is also heavier than alternative materials, which is rarely a structural issue on an established roof but is worth noting if a roof has already been modified.
EPDM (ethylene propylene diene monomer) rubber is available in self-adhesive flashing tape and pre-formed strips. It is significantly cheaper than lead and quicker to fit. For straightforward, low-profile applications - such as flashing a lean-to roof against a brick wall on a simple straight run - it can be a practical repair option. It is flexible, tolerates UV exposure well and does not attract thieves.
The honest downside is that EPDM flashing strips are not as durable as lead in complex applications. They are harder to profile tightly around three-dimensional shapes like chimney stacks, and the adhesive bond can fail if the surface was damp or inadequately prepared at the time of installation. Lifespan is typically 20 to 30 years in good conditions, less if exposed to extremes of temperature cycling.
Pre-formed aluminium flashings and lead-effect products are available from roofing merchants. They suit some situations - particularly where a very straight run is needed and appearance is less critical. However, aluminium is less malleable than lead and cannot be dressed into tight corners without cracking. For anything other than a simple application, it is not the material a competent roofer would choose.
For chimney flashings, roof valleys, dormers and any complex junction, lead remains the correct choice. It is the only material that can be properly dressed by hand into the detailed profiles those joints demand. For a simple lean-to flashing on a garden building or outbuilding, a high-quality EPDM alternative may be a reasonable and cost-effective repair. The choice depends on the location, complexity and how long you want the repair to last.
Lead work covers several distinct applications, each with its own demands:
Not all lead failures are obvious from the ground. These are the signs worth investigating:
If you are not sure, a roofer inspecting the flashings directly is the only reliable way to find out what is happening. Binoculars from the ground give a partial view at best.
There are specific details that separate sound lead work from a patch-up. Lead should be fixed in sections no longer than 1.5 metres, with a small gap at each joint to allow for thermal movement - omitting this causes the lead to buckle or crack over time. At chimney stacks, the back gutter needs to be deep enough to handle the volume of water running off the slope above it, and it should be dressed up the back of the stack high enough to prevent water overshooting in heavy rain.
Step flashings at abutments should be cut into the brick courses rather than simply plastered against the surface with mortar. The lead is tucked into a raked-out joint, then the joint is repointed - this is the correct way, and the only way that holds long-term. Simply applying mastic or mortar over the top of a flashing that is already pulling away is a temporary fix, not a repair.
Soakers at slate abutments should extend a minimum of 75mm under each slate and a minimum of 25mm up the vertical face, with the surface flashing lapping over the top of them. If soakers are missing - as they often are on older re-roofing jobs - water will get in even if the surface flashing looks intact.
As a general guide, a straightforward chimney flashing replacement on a standard two-storey house typically costs in the range of £300 to £700, depending on the size of the stack and how many faces need new lead. A more complex chimney with a large back gutter or multiple stacks will be higher. Valley re-leading on a typical semi-detached roof can cost £400 to £900. These figures cover materials and labour; scaffolding or a tower, where needed, is an additional cost. Ask for a breakdown so you can see what is included.
We carry out lead work in Bury St Edmunds and travel to neighbouring towns and villages for roofing work. Our base in Thetford means we also cover nearby places including Elmswell, Attleborough, Watton, Mildenhall, Brandon and the villages in between. If you are not sure whether we cover your area, call us and we will tell you directly.
If you have a damp patch, a lifted flashing or a chimney that has not been checked in years, call Thetford Roofers and ask for a roof survey. We will tell you what needs doing, what material is right for the job, and what it will cost - no vague estimates.
No obligation · We usually respond within 2 hours
Storm damage, active leak, damaged ridge - we aim to be on-site within 24 hours.
