When a stone-slated roof leaks, the stones are seldom the real culprit. The pegs rot, the battens soften, and a slipped stone leaves a gap that rain follows. Tile patches can add weight in the wrong places or sit proud of the stones around them.
Q2.1Should the stones be refixed or re-laid?
If a handful of stones have slipped, they can be rehung. If a whole slope is drifting, the better route is to take it off slowly, grade the stones, fit new battens and fixings, and relay the same stones in their courses, making up any losses with matching stock. That keeps the character of the roof and is usually kinder to the building than a new covering.
Q2.2Where do replacement stones come from?
Cotswold District Council's stone slate guidance reproduces an old English Heritage policy: second-hand slates should go back only onto the roof, or group of roofs, they were lifted from, because taking stone from somewhere else strips another building. We follow that thinking: your own stones go back on your own roof wherever they can, and we tell you where any replacement has been sourced.
Q2.3Can the structure below carry the weight?
Stone slate is heavy. A change to a much lighter or heavier covering alters the load on the rafters, so we look at the timbers before we propose anything. The same applies to tile that has been added over the years. Our roof repairs page sets out how we judge a repair against a larger job, and we recommend the smaller one whenever it properly fixes the fault.
Gutters and eaves belong in the same conversation. A stone-slated roof sheds a lot of water off a steep slope, and if the gutter below cannot cope, the overspill runs down chalk and rubble walling that was never meant to stay wet. Before any new covering is considered, we check that rainwater is leaving the building cleanly. Many a persistent damp patch on an old wall turns out to have a very ordinary roof-edge cause.
Photographs taken before anything comes off let the stones return in the order they came from, so the finished slope reads as the same roof.