Chapter one
Where roofs meet flint around St Mary's
Flint is the local wall, and the lead that joins a roof to it deserves a close look before anything is quoted.
St Mary's is one of the largest cruciform churches in Sussex, according to the Victoria County History, with flint rubble walls and dressings of Caen stone, sandstone and Bath stone, and reroofed again around 1970. Because the church remains in use for Anglican worship, roof work on it is handled through the faculty system, not by the council's listed building consent. Around it, the Broadwater appraisal gives flint, red and yellow brick as the typical materials, with slate or red tiles for roofs. Flint walls are uneven by nature: each nodule sits at its own angle and the mortar between is deep and irregular. That makes the junction between a roof and a flint wall one of the harder details to keep dry.
At a glance
- St Mary's is flint rubble with stone dressings
- The appraisal names slate and red tile for roofs
- Lead flashing can last over 80 years (MyJobQuote)
1.1 Lead against an uneven wall
A roof that abuts a wall is sealed with flashing, sheet lead cut into a slot in the masonry, called a chase, and folded down over the covering. On brick the chase follows a straight joint. On flint it has to follow whatever joint the wall offers, and if the lead is wedged loosely, or the pointing around it has crumbled, rain runs down behind it and the damp shows indoors some way from the cause. From the ladder we press along each run, look for lead that has lifted, split at a fold or slipped from its slot, and check the pointing above it. According to MyJobQuote, lead flashing can serve for more than 80 years, and more than 100 on higher codes, so old lead may be sound and only its fixing has failed. When that is the case, re-fixing and repointing is the smaller job, and the written quote is for that job alone.
1.2 Slate and red tile
The appraisal's two roof materials fail in different ways. Slate slips when its nails rust, or splits along its layers. Clay tile cracks, or loses the peg or nail that hangs it. On a two-storey house the eaves are in ladder reach, but the ridge and chimneys need closer inspection from the roof itself or from a tower scaffold. Where a roof has been recovered before, we lift a few tiles at the eaves to see how the underlay has aged. That thin sheet is meant to catch what the covering lets through, and when it has perished, damp reaches the timbers. Gutters matter here too: on a flint-and-brick house, a dripping joint at the gable can feed damp into the wall, so we run the gutter line in the same visit. Our lead roofing page explains the metalwork side of this.

Fig. 1 On the survey Lead lifting out of a wall joint






