Most roof leaks give you weeks of warning before the ceiling gives way. The trouble is that the warning shows up in places people do not look. Here is what we check inside a house before a ladder goes up. You can do all of it with your feet on the floor.
Start with the ceilings and cornices
Walk each room in daylight and look up. A leak stain is usually tea-coloured with a darker ring at the edge, and it grows after rain. Check the corners where the ceiling meets the wall, around the chimney, and under any skylight. Bubbling paint or a cornice pulling away from the wall means the plaster has been wet more than once.
Mark the edge of the stain lightly in pencil and write the date beside it. If it has crept past the line after the next downpour, the leak is active.
Then the roof space, with care
If you have a manhole and are steady on a stepladder, a look into the roof space tells you a lot. Take a torch and look from the manhole. Stay clear of wiring and never put weight on the plaster. If the space is tight, hot or dusty, leave it to us.
- Pinpricks of daylight between old terracotta tiles are normal. A patch of sky is not.
- Dark streaks down a rafter show the path water has taken.
- Insulation that is flattened or crusty has been wet.
- A musty smell that is stronger after rain.
Why the stain is rarely under the hole
Water gets in at one point, runs along a rafter, and drips where it meets a nail or a join. On the Californian bungalows around Coburg, the entry point is often a cracked ridge cap or a rusted valley two or three metres uphill from the stain. That is why patching the ceiling does not fix it.
When to stop and call
Do not go onto the roof. Old terracotta tiles snap underfoot and a damp roof is as slippery as ice. From the footpath, binoculars will show you slipped tiles and missing mortar well enough.
Call straight away if the ceiling is sagging, if water is near a light fitting, or if the stain grows with every shower. Put a bucket down and move the furniture.
A simple leak, such as two cracked tiles or a lifted flashing, is usually fixed from $330. Replacing a ceiling after it comes down costs several times that. If you would like it checked properly, our roof inspection with photos is $220.