Why a sealed crack is a short-term fix
A tile does its job by shedding water from one course to the next. Once it has cracked through, the crack can open a little more every time the tile warms, cools or flexes, and wind-driven rain can run along it onto the underlay below. A line of sealant or a brush-on coating over the top may hold for a while, but it sits on a piece that has already failed, and it can hide how far the crack has spread.
In general terms, then, a tile that is cracked right through is replaced, not coated. A chipped corner or a hairline craze on the surface is a different matter and needs a roofer to look closely, since some marks are cosmetic and some are not.
Roofers often tell the two apart by tapping and by looking underneath from inside the loft. A sound tile rings; a cracked one sounds dull. Daylight showing through a hole when you look up at the tile from the loft is, of course, conclusive, and worth a photograph.
What replacing one tile involves
Tiles hang on battens by a nib at the top and are usually held by nails or clips, with the courses above overlapping the course below. To remove a single tile a roofer lifts the ones above it just enough to free the broken piece, slides it out and fits the new one in the same position, then secures it and lets the neighbours back down.
Done properly, the job takes in these steps:
- Photograph the damaged area and the tiles around it before anything moves.
- Remove the broken tile and any loose pieces beneath it.
- Look at the underlay and battens where the tile sat, since a crack may have let water in.
- Fit a replacement of the right type, size and profile, and fix it so that it cannot slip.
- Check the tile line and photograph the finished spot.
Finding a good match is the harder part on older roofs, where the original tile may no longer be made. A roofer then looks for a reclaimed tile or a close modern equivalent, and the new one often goes on a less visible slope if the pattern is short.
What the work usually costs
These are national figures from published guides, offered as a yardstick. They describe other people's work around the UK and are not a price from us.
| Guide | Job | Figure |
|---|---|---|
| Which? Trusted Traders, Nov 2025 | A small job of one to six tiles | £75 to £400, ex VAT |
| MyJobQuote, Oct 2026 | Replacing roof tiles, average | Around £215 |
The Which? survey adds that London and the South East tend to push prices towards the top of its scale, and Kent falls within the South East. When a quote reaches you, look for a line saying whether VAT is in the total, because the Which? figure leaves it out.
What moves a repair within a range is access. A tile within reach of a ladder at the eaves is a different task from one high on a steep slope, where a scaffold tower is needed to work safely, and the time on site changes with it. Slate, clay and concrete also differ in how easily they are sourced, so only a survey of your own roof can fix the number.
Checking the fixings around the crack
A tile seldom cracks for no reason. Before you pay for one replacement, find out why it broke, or the next tile may follow.
- A rusted nail, or a clip that has let go, allows a tile to move and knock against its neighbours.
- Rotten timber below gives the tile no firm bearing, so it rocks.
- A crack in a line across the slope often follows someone stepping on the roof, perhaps for an aerial or gutter clearance.
- Chips on the tiles beside it may show impact from a branch or a fall of debris.
BS 5534 is the British Standard code for slating and tiling. Marley notes that its 2018 amendment widened the scope to cover normal re-roofing work, repairs included. That makes it the yardstick a roofer works to when deciding how a replacement tile is secured, even though it is a standard and not a legal requirement, so ask which fixings are going in.
See also slipped tile repair costs and tiles blown off in wind, or the wider roof repairs service.
