The short answer
With old stone and brick, the tiles or slates themselves are seldom what lets go first. Lead against a chimney or wall, the mortar along verges and ridges, and the fixings underneath fail ahead of them. Tracking down which one is the real task.
A roof that has sat on a hilltop for generations picks up small faults, and rain exploits the weakest. In Seend the older houses are stone and brick, so wall heads, chimney stacks and roof edges meet the weather first.
Q1.1Why does lead fail at the junctions?
Flashing is the lead, or in cheaper repairs mortar, that seals a roof to a wall or stack rising beside it. Lead that was fitted properly outlasts most things on a roof, yet it creeps downhill and splits, and old mortar fillets crack away from the brick. Around a stack or gable wall, a leak usually means a flashing edge has risen or a joint has opened. A soaker, the folded lead piece under each course of slate or tile against a wall, stays hidden until the covering is lifted, so we inspect the visible flashing and open up only what we must. More on stacks sits on our chimney repairs page.
Q1.2What goes wrong at verges and ridges?
The verge is the sloped rim of a roof where it ends beside a gable wall. If it relies on mortar, the bedding weathers and a gale can get under the edge. Ridge tiles on older houses were often bedded on mortar by itself. Since BS 5534:2014, a ridge cannot lean on mortar alone, so any ridge we rebed is also mechanically fixed. Up on an open hilltop, that extra grip is worth having.
Q1.3What is going on behind the covering?
Under the tiles, old battens go soft, nails rust through and the timber at the eaves soaks up damp. A tile that has slid is often a symptom of this, not the cause. When we find it, the survey photographs show you the same thing, so the written quote answers the actual fault rather than a guess.
Gutters cause quiet damage. A blocked or sagging run pours water down a brick or stone wall in place of carrying it away, and staining beneath the eaves gives it away. Clearing and realigning a gutter is a small job that can head off a bigger one.