Is one missing roof tile a problem?

Think of a pitched roof as a stack of layers. The tiles are the visible covering, and under them runs the underlay, a sheet of felt or membrane, stretched over battens, the slim timber strips the tiles are hooked onto. When a tile goes, rain can reach the underlay directly. Underlay is made to catch the odd drop that gets past the tiles, not to stand up to the weather on its own.

How soon it matters depends on the age and state of that underlay. A newer sheet may cope for a while. An old, brittle or torn one may let water through into the loft the first time it rains hard. You cannot tell from the ground, which is why a quick look in the loft after the next shower is a sensible first step. A wet patch on the insulation below the gap tells you the underlay has already been breached, and a dry loft tells you there is time to arrange a proper visit.

A gap changes the way wind moves across the slope. Gusts catch the edges of the tiles beside it, and each of those rests on its own weight plus a nail or clip. Tiles that were sound can start to shift, and one missing tile becomes three. Water driven by a gale off the sea finds the opening more easily too.

It is worth asking why the tile left at all. A cracked one may have been hit by a branch. One that simply slid out often points to fixings that have given up, which is nail sickness, a slow loss of grip as nails corrode or loosen. Our page on nail sickness explains the pattern. One tile can be a one-off, or the first warning of something larger across the same slope.

Do not climb up to cover it yourself. Roof surfaces are slippery, the edges have no protection, and a fall does far more harm than a damp loft. From inside, put a bucket under any drip, move stored items away from the area and photograph the gap from the garden, noting the date. Avoid draping sheeting over the roof from a window: it catches the wind, traps water and can drag more tiles loose.

If the weather is turning, ring us. Water getting in moves a job up our list, and a temporary cover is the first thing a roofer fits to a damaged roof before any lasting repair. If a storm caused the gap, tell your insurer too, and see our answer on whether to call a roofer or your insurer first. If you are weighing up a do-it-yourself fix, our page on DIY roof repair sets out the risks of going up without proper access.

A replacement has to match the rest in type, size and colour. Concrete and modern clay tiles are easy to find. Old clay, hand-made and reclaimed tiles can be harder, and a roofer may lift a sound tile from a hidden spot, such as behind a chimney, and fit a match there instead. Weathered colour differs from new, so a fresh tile will stand out for a season or two.

Fixing matters as much as matching. According to Wienerberger, a nail or clip is required on each single-lap tile, because gravity is not a fixing. The new tile goes in with its fixing, the batten beneath is checked, the neighbouring tiles are tested by hand and the underlay is inspected through the gap. If the cause was a crack, ask to see the broken pieces, as the pattern of the break often shows what happened. Photographs of the work go into the written quote, which shows what turned up beneath the tile as well as on top.

If the missing tile sits at the very top, it may belong to the ridge, which is a separate job covered on our ridge tile repairs page. If tiles are slipping in a row or across a slope, the roof may need more than a patch, and the page on signs a roof needs repairing shows what else to check.

The cost for one tile is modest, because the work is mostly access and diagnosis. Typical rates are on the page for repair cost per square metre, and the full service sits under roof repairs. Our verdict says whether a repair is enough, and the proposal covers only what the fault demands. If the neighbouring tiles are sound, you are told so, and shown.