Lead flashing is one of the most important elements in any roofing system, designed to prevent water from penetrating joints and gaps where the roof meets walls, chimneys, or other structures. When installed correctly, flashing provides long-lasting protection against leaks. However, over time, even the most durable leadwork can deteriorate. Recognising the early signs of cracked or failing flashing can save homeowners from extensive water damage later on. At Foots Cray Roofing Repairs, we help property owners across Foots Cray and South East London identify and resolve these issues before they become serious.
What Is Lead Flashing and Why It Matters
Lead flashing acts as a weatherproof seal at points where different sections of your roof meet, such as:
- Around chimneys and skylights.
- Along roof valleys and junctions.
- Where roofs meet brick walls or extensions.
- Around dormer windows or parapets.
Its purpose is simple but vital — to direct rainwater away from vulnerable joints and prevent moisture from seeping into the building’s structure. When flashing starts to crack or lift, water can easily enter beneath tiles or slates, leading to leaks, damp, and structural decay.
Common Causes of Flashing Damage
Flashing failure can occur for a number of reasons, many of which are due to age and environmental exposure. Some of the most common causes include:
- Thermal expansion and contraction: Temperature changes cause lead to expand and contract. Over time, this movement can lead to splits or cracks.
- Poor installation: If flashing was not fitted or secured correctly, it may pull away from the roof surface or mortar joints.
- Weather exposure: Harsh wind, rain, and frost accelerate deterioration, especially on older roofs.
- Movement of the building: Subsidence or minor shifts in the structure can dislodge flashing or open up small gaps.
- Oxidation and corrosion: Although lead is naturally resistant to corrosion, years of exposure can still cause degradation on the surface.
How to Identify Cracked or Failing Lead Flashing
Catching flashing issues early can prevent costly roof damage. Here are some key signs to look out for:
1. Visible Cracks or Splits in the Lead
Cracks are one of the clearest indicators of ageing leadwork. These typically appear as thin, dark lines or visible gaps. In severe cases, you may notice small pieces of lead lifting or curling at the edges.
2. Loose or Lifted Flashing
If the flashing appears detached from the mortar or roofing material, water can easily penetrate underneath. Lifting often occurs where flashing has been fixed incorrectly or where weather conditions have loosened the seal.
3. Gaps Between Flashing and Brickwork
Mortar joints can crumble over time, leaving noticeable spaces between the flashing and the wall. These gaps allow water to run behind the lead instead of being directed away.
4. Water Stains on Interior Walls or Ceilings
Damp patches inside your home, especially around chimney breasts or upper corners, can indicate failed flashing. Water may have found its way through small openings and begun to soak internal materials.
5. Corrosion or Discolouration
A dull white powder or streaking on the lead’s surface could indicate oxidation or fatigue. While some surface patina is normal, excessive discolouration may suggest deeper deterioration.
6. Drips or Leaks During Rainfall
If water drips from the top of a chimney breast or wall junction during wet weather, it’s often due to flashing that has cracked or separated from the structure.
Why Ignoring Flashing Problems Is Risky
Lead flashing issues rarely fix themselves — they tend to worsen with each rainstorm or freeze-thaw cycle. Left unchecked, even a small crack can:
- Allow water to enter the roof space.
- Cause rot in timber rafters or battens.
- Lead to damp and mould growth inside the property.
- Weaken mortar joints and surrounding masonry.
A professional inspection from Foots Cray Roofing Repairs ensures that any damage is properly assessed and the correct repairs are carried out before the problem spreads.
Maintaining Flashing to Extend Roof Life
To prevent flashing damage from recurring, regular maintenance is essential. Homeowners should:
- Inspect the roof annually, particularly after winter.
- Remove debris and moss that traps moisture against the lead.
- Repoint mortar joints when they begin to crack or erode.
- Ensure proper ventilation in the roof to reduce condensation buildup beneath flashing.
- Arrange professional inspections if any movement, cracking, or discolouration is noticed.
Proper upkeep not only prolongs the lifespan of your lead flashing but also safeguards the rest of the roof from unnecessary damage.
How Professional Roofers Assess Lead Flashing
Specialist roofers use both visual checks and moisture detection methods to assess flashing integrity. At Foots Cray Roofing Repairs, our team examines all vulnerable areas, including:
- Chimney bases and step flashing.
- Valleys and roof intersections.
- Eaves and gutter junctions.
- Flashing around skylights or dormers.
By pinpointing the exact location and cause of failure, we can recommend targeted, long-lasting repairs to restore full waterproof protection.
Conclusion
Cracked or failing lead flashing may start as a minor roofing issue, but it can quickly escalate into serious water damage if ignored. Regular roof checks, especially after heavy weather, allow homeowners to catch early signs of deterioration before leaks occur.
For homeowners in Foots Cray and South East London, Foots Cray Roofing Repairs provides expert flashing inspection and repair services to keep your roof watertight and reliable. With proper care and professional attention, your lead flashing can continue protecting your property for many years to come.
Call us on: 0208 059 2692
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