Somebody points out a tile that has slid down your roof. Nothing is dripping in the bedroom, so the obvious thought is to leave it until the weather improves. Sometimes that is the right call. Often it is not, and the reason is what sits under the tile rather than the tile itself.
What a slipped tile actually exposes
Under the tiles is roofing felt — the real waterproof layer — then battens, then rafters. A single slipped tile does not usually let water into the house, because the felt catches it. What it does is expose that felt to sunlight and weather it was never meant to see.
On a house built before about 1980, that felt is bitumen and it is already brittle. A few months of direct rain and UV on an exposed patch and it perishes. Now water is on the batten, and the batten is untreated softwood. Then it is on the rafter.
Why one tile is rarely just one tile
Tiles slip for a reason, and the reason is nearly always the nail or the peg that held it. If those are corroded on one tile, they are the same age on every tile around it. When we go up for one slipped tile, we expect to find two or three more that are on their way, and the honest thing is to tell you that and do them at the same time rather than come back twice.
The two-minute check from the ground
Get twenty metres back with binoculars or your phone camera zoomed in, and look for:
- Dark or shiny patches where felt is showing through
- A line of tiles that is no longer straight — the whole course sagging means battens, not tiles
- Moss banked up behind a tile, which lifts it and holds water against it
- Mortar missing from the ridge or the verge, which is a bigger job than a tile and a more urgent one
- Grit in the gutters, which is concrete tiles breaking down and means age, not damage
Inside, go into the loft on a bright day with the light off. Daylight through the felt is a hole. Dark staining on a rafter is water that has been coming in for a while.
So: now, or spring?
Now if the felt is visibly exposed, if there is any staining in the loft, if it is above a valley or a chimney, or if the house was built before 1980.
It can wait if the tile has slipped but is still lapping the one below, nothing is visible in the loft, and the roof is modern with breathable membrane. Get it done before the winter storms anyway — one gale turns a slipped tile into a missing one, and a missing one into a hole.
Please do not go up there
Most roofing injuries are not falls off roofs. They are falls off ladders, by people who have been on a ladder a hundred times. Roof tiles break under a knee, moss is like ice, and a roof looks a great deal steeper from the top of it. It is a hundred-and-fifty-pound job for someone with a tower and the right kit.
Want it done rather than done yourself?
We cover Chelmsford and all of Essex, and we take the small jobs as well as the big ones. Price it on the estimator, or just ring and ask.