Ridge tile repairs and dry ridge in Worthing

Traditionally those caps were bedded on a sand and cement mortar, laid under each tile and pointed along both edges. Mortar is hard but brittle. It shrinks as it cures, it soaks up water, and frost and thaw work on it every winter while the roof flexes in the wind. After enough years it cracks, loosens and falls away in crumbs, and the tile it held begins to rock. A rocking tile lets rain in at its joints and can work free altogether in the next hard blow.

1.1 What a failing ridge looks like

From the garden or the pavement, look along the ridge line. It should run straight. A tile sitting crooked, a visible gap between neighbours, a missing end cap at a gable or a run that has slipped sideways all point to bedding that has gone. Pale crumbs of mortar in the gutter or on the path tell the same story. Moss growing in a line along the pointing is another clue, because it takes hold where mortar has cracked and holds damp. Stay on the ground for this. A phone photo with the zoom on is enough to start with.

Indoors, the evidence is gathered where the rafters meet at the apex. We look at the timbers there for dark staining, check the underlay beneath the ridge for tide marks and pools, and look for daylight where there should be none.

1.2 Why the leak shows up somewhere else

A leaking roof caused by a faulty ridge rarely drips at the ridge. Rain that gets under a tile at the apex lands on the underlay and runs downhill along the rafters until a nail hole, a lap or a joint lets it through. The stain on a bedroom ceiling can sit a long way from the fault above it. That is why a roof leak chased from the stain so often ends in the wrong repair, and why we start at the highest wet point in the loft and follow the water back before anyone prices anything. Where the cause is the ridge, you can judge the repair from the photographs.

6.1 Planning, listed buildings and conservation areas

Maintenance that leaves the outside of the house looking the same is not treated as development, so like-for-like ridge work seldom needs planning permission. A listed building is different. Adur & Worthing Councils say consent is needed when repairs are made in anything other than matching materials, while the South Downs National Park Authority says routine upkeep and small repairs made like for like, in place, do not need it, though replacing historic fabric does. Article 4 directions reach further in a few streets. In Old Shoreham and in Kingston Buci, the Article 4 directions take away permitted development rights over roof alterations, roof coverings included, when the house looks onto a road or public right of way. The Warwick Gardens conservation area direction in Worthing covers changing how a roof slope looks, in shape or material, where it faces a road or open space. Check with the Adur & Worthing planning team before changing a ridge's material or style in those streets. A ridge can shelter bats or nesting birds, both protected, so it is checked before any tile moves.

6.2 When a gale is behind the damage

Where a gale has lifted tiles, your insurer may need to hear about it. The Financial Ombudsman Service says it asks whether there was a storm on the date the damage happened and whether the damage is consistent with storm damage, and adds that policies commonly exclude damage built up over time. Which? reports that insurers often lean on a minimum gust speed to define a storm, and uses a poorly kept roof letting water in as its wear-and-tear example. Photographs of the fault, the date and the weather help whatever the outcome, and your insurer decides what it will pay.