Why is my roof leaking? The most common causes
The main reasons roofs leak, from slipped tiles to failed flashing, and how roofers trace them.
The usual suspects
Slipped or broken tiles, failed lead flashing at chimneys and walls, worn valleys, blocked gutters, perished underlay and splits in flat roofs account for most leaks we see.
Why the stain isn't always below the leak
Water runs along felt and timbers before dripping, so a ceiling stain can be a metre or more from the actual entry point.
How it's traced
A roofer checks the loft and the roof surface, looking at junctions, flashings and valleys first. Noting when the leak happens – heavy rain, wind direction, cold mornings – helps a lot.