In short
Most leaks with no visible damage come from a junction, not the tiles: a lead flashing that has lifted, a cracked chimney flaunching, a blocked valley or a ridge that has lost its mortar. Water then tracks along the felt or a rafter and shows up on the ceiling well away from the hole. Finding it means somebody going up and looking, not guessing from the ground.
This is a job for our Roof survey & report service.
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Where the water is actually getting in
On the roofs we survey around King's Lynn, Downham Market and Swaffham, a leak with no obvious damage is nearly always at a detail rather than in the open field of the roof. MyJobQuote's 2026 leak repair guide lists the same culprits we see every week: flashing that has deteriorated around chimneys and junctions, ridge tiles loosened by wind or failed mortar, valleys blocked or worn thin, and chimney mortar that has washed out. Broken tiles are on the list too, but they are the easy one because you can see them.
Why the stain is nowhere near the hole
Water does not fall straight down. It gets under the covering, lands on the underlay and runs downhill until it finds a nail hole, a tear or a lap it can drip through. On an older roof with bitumen felt that has gone brittle, the drip point can be two or three metres from the entry point. We have traced a stain over a bedroom window to a chimney tray on the other side of the ridge.
The things that fool people
- Condensation. A wet patch that appears on cold, still mornings and not after rain is usually the loft, not the roof. We check the loft before we check the tiles.
- Wind-driven rain. Pantile roofs on the coast at Hunstanton let rain under the laps in a south-westerly. If the underlay is sound it drains away. If it is torn, you get a leak that only appears in certain weather.
- Gutters. An overflowing gutter soaks the fascia and the wall head, and the damp shows inside as a "roof leak" on the top of the wall.
How we find it
- We ask when it leaks. Every time it rains, only in wind, or only in cold weather each point to a different cause.
- We look in the loft first with a torch, following the water back uphill from the wet patch to the highest wet point.
- We get on the roof, photograph the details above that point, and lift tiles if we need to see the underlay.
- We write down what we found, with the photographs, so you can see it yourself.
The HSE's roof work guidance is blunt that falls are the biggest killer in construction, and that short jobs on a pitched roof still need a secured ladder and a proper roof ladder. That is why we do not diagnose from the pavement and why we do not recommend you go up yourself.
