Where Is My Roof Leaking? How to Track It Down

Begin in the loft

Go up with a torch while it is raining, or just after. Find the wet patch above the stain and follow the damp uphill.

• Shiny or dark streaks on rafters
• Drips hanging from the felt
• Pinpricks of daylight
• Damp, flattened insulation

Then look from the ground

Stay off the ladder. Binoculars from the garden or across the road will show most faults.

• Tiles or slates out of line
• Lead that has lifted at a chimney or wall
• Gaps in the mortar along the ridge
• Gutters overflowing at one spot

Use the weather as a clue

A leak that only appears in driving wind usually points to flashing, ridge tiles or the roof edge. One that drips in any steady rain is more likely a broken tile, a valley or a flat roof.

Rule out condensation

Damp in the loft on cold, dry days is often condensation and not a leak. That is a ventilation problem with a different fix.

When to get a roofer

If you cannot see the cause, or water is near wiring, call a roofer. A good repair starts with finding the real entry point.