Lead valleys, chimney stacks and the wear of old fixings
On a Victorian villa, the roof is a collection of slopes joined by valleys and capped with tall stacks. Lead valleys and flashings work hard, and where they split or lift, water enters behind the slates. Stack pointing weathers too, and old rendered stacks can let rain run down the chimney breast.
The other long-term weakness is the nails holding the slates. Iron nails rust, and slates then slip even though the stone is sound. A hilltop gale finishes the job. Re-fixing with durable nails or clips and replacing damaged slates usually costs far less than stripping the whole roof, and we say clearly when that is possible.





