Why Do Roofs Start Leaking After Heavy Rain in Neath?

Why the Leak Is Not Where the Stain Is

Water entering high on a roof can run along battens, rafters and the top of the ceiling before it drops through. A damp patch on a landing ceiling can come from a defect several metres away.

This is why we work backwards from the symptom rather than repairing straight above the stain.

Common Causes After Heavy Rain

• Slipped or broken slate and tiles. Even a small gap lets driven rain reach the underlay.
• Damaged or lifted flashing. The joints around chimneys, walls and roof windows are common weak points.
• Blocked or failed valleys. Leaves and debris can make water back up and find its way under the covering.
• Displaced ridge tiles. The highest point takes the strongest wind and rain.
• Blocked gutters and downpipes. Overflowing water can get behind fascias and into the eaves.
• Extensions and junctions. Where an extension meets the main roof is a common place for leaks.

Why Storms Show Up Old Problems

Wind and heavy rain often reveal a defect that had been developing quietly. Mastic or roofing cement used to patch flashing sets rigid, while the roof and masonry move at different rates, so it cracks. Properly dressed lead moves with the building.

How a Roofer Finds the Leak

• Ask where and when the water appeared and in what weather.
• Check the roof covering, ridge, valleys and junctions.
• Inspect flashings, gutters and any penetrations.
• Check the roof space for damp timber or stained underlay where it is safe to do so.

What to Do Now

Protect belongings, put a bucket under the drip and call. T & T Roofing South Wales is based in Neath and quotes free and without obligation.

See also storm damage roof repairs in Neath or the wider South Wales storm damage page.