Lead roofing and leadwork in Bognor Regis

Most leaks that start in lead begin at a flashing that has lifted, split or lost its pointing, not in the sheet itself.

On a pitched roof the lead that matters most sits where the slope meets something vertical. A flashing is a strip of lead bridging the gap between roof and wall. Its top edge is turned into a raked-out mortar joint, held with small lead wedges and pointed, while its lower edge lies over the tiles or slates. Where a wall runs up the slope, as at a gable, soakers are used too. A soaker is a small piece of lead folded to an L-shape, tucked under one course and turned up the wall, so every course has its own waterproof step. The flashing then covers the tops of the soakers and finishes the joint. Where the roof slopes down past a wall rather than up it, the flashing steps down in sections, each one overlapping the next.

2.1 Chimney stacks

A chimney is a lead job from top to bottom. On the downhill face an apron covers the base of the stack. Along the sides run stepped flashings, cut to follow the brick courses. On the uphill side sits a back gutter, a small lead channel that sends water round the stack instead of letting it bank up behind. Tall stacks take the weather on every face, and when the lead round one fails the damp often shows indoors on the breast of the chimney, well below the roof. That is why our chimney repairs work treats the flaunching, the pointing and the lead as one job rather than three. Flaunching is the sloped mortar that caps the stack round its pots, and when it has cracked it is renewed on the same visit.

2.2 When a repair is enough

Lifted lead can sometimes be re-dressed and the joint repointed, and a short crack can be cut out and a new piece let in. A repair stops making sense when the lead has been patched several times, has split along its folds, or is too thin for the length it covers. We photograph the fault, show you what we found and say which of those it is. MyJobQuote puts patching chimney leadwork at £150 to £250 and a full renewal at £350 to £460 without scaffolding. With scaffolding the renewal figure rises to £700 to £920, and renewing is often the better spend then, because the scaffold is already standing. Each stage is photographed. Our guide to lead flashing shows each type in turn.

Self-adhesive tape and mastic have their uses as a stopgap, but a tape-covered flashing hides a fault rather than ending it, and it must come off before the lasting repair can start. Ask to see photographs of the lead before and after, so you know exactly what was done. On slate roofs, the lead and the slates around it should be assessed together, since a flashing is only as secure as the courses it sits on. Our slate roofing page covers that side of the work.

Away from the chimney, lead lines the valleys and covers the flat tops of dormers, bay windows and porch canopies.

Where two slopes run into each other at an inside corner, the junction is a valley, and both slopes send their rainwater down it together. Lead-lined valleys carry that water in one channel, with the tiles or slates cut back at each side and laid over the lining. They are hard to see from the ground and easy to forget, and leaves, moss and grit settle in them. When a lead valley leaks, the usual culprits are a crack in the lining, an edge that has lifted, or debris holding water in the channel until it finds a way through.

4.1 Valley repair or replacement

Reaching a valley lining means lifting the tiles or slates along both sides, so even a modest fault is not a ladder-and-five-minutes job. That shapes the verdict. A short crack in a lining that is otherwise sound can be repaired. A lining that has split in several places, or that was cut in lengths beyond what its thickness suits, is better replaced, because the tiles are already lifted and the new lead can run in one clean length. We tell you which it is, with photographs of the lining, before any price. Our guide to lead valley repair and replacement compares the options in more detail.

4.2 Dormers and bay window roofs

A dormer carries more lead than it appears to from the street. The cheeks are the side walls, the top is usually a small flat roof, and aprons seal the roof slope to the window below. Each joint is lead, and each one is a place where wind-driven rain can find a gap. Bay windows and porch canopies are the same on a smaller scale: a flat or shallow top, a flashing where it meets the wall, and an edge that must throw water clear. Arun's guidance on The Steyne describes terraces of two and three storeys with bay windows and balconies, so these small lead roofs are part of the street as well as the weatherproofing. Dormer lead takes wind from several directions at once, and its soakers sit under the cill and the cheek tiles, which are fiddly to reach. Where a dormer roof is old, we often find the cheek lead has slipped on its fixings and the top has ponded, so we test the fall by eye and with water. Renewing the cheeks, the apron and the top as one job makes more sense than patching them three times in as many winters.

Lead porch roofs have a local history too. Arun's statement for the Craigweil House conservation area in Aldwick records that Wychwood, built from 1934, has leaded roofs to a number of its entrance porches. A small lead canopy like that is easy to overlook in the survey of a larger roof, so we always check porches, bays and lean-to tops as well as the main slopes. Tell us about any bay roof that has marked the ceiling below, however faintly. A flat-topped porch needs a fall to drain, like any other lead roof.

Lead can outlast the roof around it, but only if the pointing, fixings and drainage beside it are looked after.

Lifespans for lead are long. MyJobQuote says a lead flashing can last for over 80 years, and the home improvement guide Less puts a lead flat roof at 50 to 100 years. Treat those as typical ranges, never promises: they describe lead that was laid well and kept clear of debris. In practice the pointing, the fixings and the tiles or slates around the lead often need attention before the sheet does, so we look at all of them. Our answer on how long a lead roof should last goes through the same sources.

6.1 Keeping lead in good order

Maintenance is mostly clearing. Leaves and moss collect in valleys and box gutters, and standing water finds weak joints. A look after autumn gales and after a long wet spell catches most problems while they are still small, and debris cleared from a valley leaves the site with us. Cracks, lifted edges and missing pointing are cheap to fix when found early and expensive when water has been in the wall for a winter. Gutters and downpipes beside the lead deserve the same check, since an overflowing outlet soaks the wall the flashing is fixed to.

6.2 If lead has been stolen

Stolen or torn lead leaves a roof open to the weather, so making the roof safe comes first. Tell your insurer promptly, photograph what has gone, keep receipts for any temporary cover, and keep anything damaged until the insurer has seen it, which is the advice Which? and the Institution of Structural Engineers give for storm damage. We make the roof weathertight first and then survey for the permanent repair. Whether a claim is paid is for the insurer to decide.

6.3 Planning, listed buildings and building control

Replacing lead like for like normally does not need planning permission, because under section 55 of the Town and Country Planning Act 1990, works that do not materially affect a building's external appearance are not development. A listed building is different: alterations that affect its character need listed building consent, though the South Downs National Park Authority states that routine upkeep and small like-for-like repairs do not. The Steyne and Waterloo Square conservation area, in Bognor, dates from August 1979 and was extended in July 1994, and the Aldwick Road area followed in July 1994; none of Arun's Article 4 directions in the town takes roof rights away. For a listed or protected building, ask the planning team at Arun District Council before work begins.

Lead is common on church roofs, and the consent route depends on the denomination and the building. Where a Church of England building is still in use, it goes through the faculty system, while a closed church, or one vested in the Churches Conservation Trust, needs listed building consent from the council. Under Approved Document L a new waterproof covering on a flat roof is renovation, so a new lead flat roof may bring its insulation into play; building control or your roofer can confirm. Bats are protected, which is why we look for roosts before anything is stripped.