Why Lead Flashing Fails Before the Roof Does
Many roof leaks in Hammersmith and Fulham are not caused by a failed roof covering. They start at the junctions: where a roof meets a chimney, parapet wall, dormer, rear extension or neighbouring property.
Those junctions usually rely on lead flashing. When the lead lifts, cracks, pulls out of mortar joints or has been patched badly, rain can track behind otherwise sound slates, tiles or flat roof membranes.
Common Flashing Problems in West London Homes
Chimney Flashing
Older chimney stacks often have worn mortar, loose soakers or tired stepped flashing. Water can enter around the stack and appear as staining on chimney breasts or upstairs ceilings.
Parapet Wall Details
Parapets are common on period terraces and mansion blocks. If the flashing, coping stones or abutment details fail, water can sit against brickwork and find its way inside.
Extension Roof Junctions
Rear extensions often meet original brick walls. Poorly cut chase lines, shallow cover flashing or split sealant can create repeat leaks after heavy rain.
Flat Roof Edge Details
Flat roofs need careful edge and upstand detailing. If flashing is too low, loose or poorly dressed, wind-driven rain can get underneath the waterproof layer.
Signs You May Need Flashing Repairs
Watch for damp patches near chimney breasts, staining high on party walls, leaks that only appear during wind-driven rain, loose mortar around leadwork, visible gaps from ground level or repeated patch repairs that do not last.
A leak does not always appear directly below the fault. Water can travel along timbers or behind plaster before showing indoors.
Repair or Replace?
Small faults can sometimes be repaired by refixing lead, repointing chase joints or replacing short sections. Full replacement is more sensible when the lead is split, badly installed, too short, heavily patched or failing across several junctions.
Good flashing work should be mechanically sound, correctly lapped and neatly pointed. Sealant alone is rarely a permanent answer.
Why Professional Access Matters
Leadwork looks simple from the ground but needs safe access and careful handling. Walking on old slates or tiles can create new damage, and poorly dressed lead can fail quickly through thermal movement.
A roofer should inspect the surrounding roof covering, brickwork, gutters and valleys at the same time. Flashing repairs work best when the full water path is understood.
Book Lead Flashing Repairs
Hammersmith & Fulham Roofing handles chimney flashing, parapet details, roof abutments, flat roof upstands and leak tracing across Hammersmith, Fulham, Brook Green, Shepherd's Bush, Kensington and nearby West London areas.
**Call 020 8528 3900** for practical advice and a clear repair plan.