7 signs your roof is leaking (and what to do first)

Most of the leak call-outs we get in Dublin have been building for months. The roof was dropping hints the whole time, but the hints are easy to miss until a stain appears on the ceiling. Here are the signs we look for, in the order you’re likely to notice them.

1. Slipped, cracked or missing slates and tiles

Stand across the road and look at the roof after a windy day. A slate sitting lower than its neighbours, a gap in a row, or bits of broken tile in the garden are all early warnings. One slipped slate is a small repair. Leave it and water tracks under the ones around it, rots the batten and takes a bigger patch with it.

2. Moss build-up and blocked gutters

Moss holds water against the roof and wicks it under slates and tiles. When it drops off it blocks the gutters, which then overflow back under the eaves. If your gutters spill over in heavy rain, that water is going somewhere it shouldn’t.

3. Staining around the chimney

Chimneys are the number one source of leaks on Dublin roofs. Look for damp patches on the chimney breast inside, especially upstairs, and crumbling mortar or lifted lead flashing outside. The fix is usually re-flashing or repointing, not a new roof.

4. Damp in the attic

Get up in the attic with a torch on a wet day. Look at the underside of the felt and the timbers for dark staining, drips or daylight. Perished felt (the old black bitumen type that tears like paper) is a sign the roof is near the end of its life.

5. Ponding on a flat roof

Water still sitting on a flat roof two days after rain means the falls are wrong or the deck has sagged. Ponding water finds every weak seam eventually. Blistering, cracking at the edges, or a soft spot underfoot are the next stage.

6. Bubbling paint or peeling wallpaper upstairs

Water often runs along a rafter or ceiling joist and shows up a long way from where it came in. A patch of bubbling paint at the top of a wall or near a window reveal is often a roof leak, not a plumbing one.

7. Higher heating bills

Wet insulation stops working. If the upstairs rooms have got noticeably colder, the insulation in the attic may be holding water.

Repair or re-roof?

Most of the signs above are repairs, not replacements. We’ll only recommend a re-roof when the felt and battens are gone and you’d otherwise be paying us to patch the same roof every winter. Either way, you’ll get photos of what we found and a written price before anything happens.