11/08/2026
If you have a roof leak, the tiles are probably not the problem.
The large majority of leaks we attend start at a junction: where the roof meets a chimney stack, where a lower roof runs into a taller wall, around a dormer, or in a valley where two roof planes drain together. All of those are weatherproofed with lead flashing, and the flashing fails long before the surrounding tiles do.
This is genuinely useful to know, because it changes what you ask a roofer for. Someone quoting to re-tile a whole slope when the actual fault is a cracked chimney apron has sold you an expensive repair that will not fix anything.
A tiled slope is forgiving. Every unit overlaps the one below, so the geometry sheds water and nothing needs to be watertight in isolation. A junction has no such redundancy. It is one continuous barrier, and a single split or lifted edge lets water straight in. These are also the points where thermal movement concentrates, since masonry and timber move at different rates and the lead absorbs that difference every day for decades.
Signs to watch for: a damp patch on an upstairs ceiling near a chimney breast, staining on the chimney breast inside the loft, lead that has curled or pulled out of a mortar joint, white salt deposits on internal brickwork, and moss built up in a valley channel. A leak that only appears in certain conditions is not a minor one, it is a directional fault.
One thing you can check from the ground. Cement smeared where the roof meets the stack, instead of proper lead, is a patch rather than a repair. Cement is rigid, the junction is not, and it cracks every time.
Free inspection, zero deposit, 10-year guarantee.
Read more in our blog: https://wareingmckenna.co.uk/lead-flashing-and-valleys-where-roof-leaks-actually-start/
