A slipped, cracked or missing tile is usually a small repair, but it should be fixed soon. The gap lets rain reach the underlay and roof timbers, and wind can get under the tiles next to it. Most slipped tiles are caused by worn-out nails, pegs or battens, storm damage or frost. A roofer can normally refix or replace a few tiles in a single visit, as long as the cause is dealt with too.
Why tiles and slates slip
Tiles rarely fall off for no reason. When one moves, it is usually a sign that something underneath has worn out.
Rusted nails on slate roofs
Natural slates are held on by nails, often two per slate. On older roofs these nails rust through over time, a problem roofers call nail fatigue. Slates then slide down one by one, often leaving a neat gap and a slate sitting in the gutter. If several slates have slipped, more are likely to follow.
Worn pegs, nails and battens on clay tile roofs
Old clay plain tiles hang on the battens by small nibs or wooden pegs, with some nailed. Pegs rot, nails corrode and battens go soft, so tiles drop out of line. The tiles themselves are often still sound.
Storm damage
Strong gusts can lift tiles at the edges of the roof, around ridges, hips and verges, where the wind pressure is highest. Once one tile goes, the wind can get under its neighbours. See our guide to what to do after storm damage.
Frost and age
Water soaks into older tiles and expands when it freezes. Over many winters this can crack tiles or make the surface flake. Concrete tiles can also get brittle with age.
Foot traffic and impact
Tiles crack when people walk on them, for example to fix an aerial or clean a gutter. Falling branches and debris can also break them.
Why it matters
A single slipped tile might not leak straight away, because most roofs have underlay beneath the tiles. But older roofs may have tired underlay, or none at all, and even good underlay is not designed to be the main barrier. Left alone, a gap can lead to:
- rain reaching the battens and rafters, which can rot
- damp patches on ceilings and walls
- more tiles lifting in the next storm
- a bigger, more disruptive repair later
If you can see daylight in the loft or a damp patch on a ceiling, get the roof checked soon, as there may be other causes too.
How slipped and missing tiles are fixed
Refixing a few tiles or slates
For the odd slate, a roofer will usually remove the broken nail and refix the slate with a discreet metal clip, often called a tingle, or a modern fixing hook. Slipped tiles are lifted back into place and fixed. Cracked tiles are swapped for matching ones, which may be reclaimed for older roofs.
Fixing every tile properly
The current British Standard for slating and tiling, BS 5534, expects tiles and slates to be mechanically fixed (nailed or clipped) rather than relying on their own weight, with extra fixings at the edges of the roof. When a roofer replaces tiles, they should be fixed to this standard.
When a patch repair isn't enough
If tiles are slipping all over the roof, the problem is usually the fixings or battens, not the tiles. In that case, a roofer may suggest stripping the roof, saving the good tiles or slates, and relaying them on new battens and breathable underlay. Our guide to deciding between repair and a new roof explains how to weigh this up.
Rules to be aware of
Replacing a few tiles is a repair and does not normally need building regulations approval. If you re-cover a large part of the roof, building regulations may apply and you may need to improve insulation. If your home is listed or in a conservation area, use matching materials and check with your local council before changing anything. Our guide to building regulations when you re-roof has the detail.
Should you fix it yourself?
We would advise against it. Roof work is dangerous without scaffolding or proper access equipment, and walking on tiles often cracks more of them. A roofer can also spot the cause, such as rusted nails or a worn ridge, which is easy to miss from a ladder.
In Essex, Hertfordshire and Cambridgeshire
The causes of slipped tiles vary a lot across the three counties.
- Open fen: In Ely and March, flat, open fenland means roofs catch the wind from every direction. Storms lift ridges and verges, and on March's many older slate roofs the nails rust through so slates slip one by one.
- Old clay tile towns: In Saffron Walden, many roofs have old clay plain tiles whose pegs and nails wear out. Often the good tiles can be saved and relaid on new battens and breathable underlay, keeping the original look.
- The coast: In Clacton-on-Sea, strong winds and salt air lift ridge and hip tiles, loosen verges and rust metal fixings faster than inland.
- Thames-side terraces: In Grays, slates on Victorian terraces slip as their original nails rust through, and winds along the river lift ridge tiles.
- 1930s roofs: Many Potters Bar homes from the 1930s still have their original tiles and battens, often with no proper underlay, so worn nails and battens let tiles slip.
How First4Roofcare can help
We refix and replace slipped, cracked and missing tiles and slates, and we look for the reason they moved. Find out more about our roof repairs and tiled roofs. If you have spotted a gap or a tile in the garden, book a free roof survey and we will tell you what we find.