Chapter one
Where Barcombe's flint walls meet their roofs
Flint is lumpy by nature, so the join between a flint wall and a tiled roof has to be made to fit, stone by stone.
St Mary's church, according to the Victoria County History, is built of flint with sandstone dressings and has tiled roofs; its nave dates from about 1100 and its west tower was added in the 13th century. Flint walls are lumpy by nature. No two stones sit alike, and a roof that has to meet such a wall cannot rely on a straight cut and a bead of sealant. The junction has to be made to fit, stone by stone, and that is where a good many leaks begin. Any house with a flint gable or garden wall running into its roof shares the same weakness on a smaller scale. The sandstone dressings add more joins, at corners and around openings, and each one is a place where a roof edge or a gutter has to be fitted to the stone.
At a glance
- St Mary's is flint with sandstone dressings
- Lead must follow an uneven flint face
- Sealant over a failed joint only delays the leak

1.1 Where roof and flint wall meet
Along a flint wall the roof edge is sealed with a flashing, lead dressed from the wall down over the tiles. Its top edge goes into a joint between the flints, so the wall's mortar matters as much as the lead. When that mortar crumbles, the lead loosens and rain slips behind it, often travelling down the inside face of the wall before it appears as a damp patch. For this reason we trace stains upwards from the ceiling and outwards across the wall instead of blaming the nearest tile. The sequence for putting a joint right is set out in the panel below, and the photographs we take beforehand show you exactly which stretch has failed.

1.2 Tiled roofs, the church and the street
While St Mary's is used for worship, work on its roof follows the Church of England's faculty process under the ecclesiastical exemption, not council consent. For houses nearby the question is different. A covering that matches its neighbours keeps the character of the street, and a listed house may need consent for anything else. Tile style is part of that: handmade plain tiles carry a gentle camber and a variation in shade, and a flat machine-made tile of similar colour can still look wrong on a roof of this age. Where tiles beside a flint wall have slipped, we check the nails and battens, the slim timber laths the tiles hang from, then fix matching replacements. Our pitched roofing page covers full re-tiling when a repair is not enough.
Re-making a lead joint against flint
- Open the joint Rake out loose mortar from the flint bed joint to a depth that will hold the lead.
- Dress the lead Form new lead to follow the wall's uneven face and lap it over the tiles.
- Wedge and point Fix the upper edge with lead wedges and point it in a mortar suited to the wall.
- Test the lap Confirm water sheds over the covering instead of running behind the lead.







