Why Is Water Coming Through My Ceiling?

First, Regardless of Cause

If water is at or near a light fitting, a ceiling rose, a downlighter or anything wired, turn that circuit off at the consumer unit. If you are not sure which one and water is spreading, turn the whole board off until somebody competent has looked.

If the ceiling is bulging, sagging or dripping from a single point, keep everybody out of that room and shut the door. Trapped water is heavy and ceilings give way without warning.

Get a container under it - a bin rather than a bowl - and move what you can.

That applies whatever is causing it, so do it before working out which of the following you have.

Six Causes

1. The roof. Follows rain, particularly wind-driven rain from one direction. Usually stains rather than pours. Worse in some weather than others.

2. Rainwater goods. Follows prolonged heavy rain. More often shows on a wall than a ceiling, but water going behind a gutter can reach a ceiling at the junction with an external wall.

3. Plumbing. Clean water, no correlation with weather at all, and often continuous rather than intermittent. A leaking pipe in a floor void, a failed seal on a shower or bath, or a washing machine or dishwasher on the floor above.

4. An overflowing cold water tank or a failed ballvalve. Clean water, in the loft, no rain required. The classic sign is an overflow pipe dripping outside the house - if you can see one running, that is your answer.

5. Condensation. Cold dry weather rather than rain. Beads of water on nails, nail plates and the underside of the underlay, spread over an area rather than concentrated at a point. Worse above bathrooms and kitchens, and worse after loft insulation has been topped up.

6. A frozen or split pipe. Appears during or just after a hard frost, often as the thaw arrives, and can be sudden and heavy.

How to Tell Them Apart

Is it raining, and has it been? No rain for days and water coming through means plumbing or a tank, not the roof.

Is the water clean or dirty? Water that has come through a roof picks up dust, soot and staining from insulation and timber - it is usually brown or grey and it marks. Clean, clear water is far more likely to be plumbing or a tank.

Is it continuous or does it stop? A roof leak stops when the rain stops, or shortly after. A plumbing leak does not.

Which room is above it? A bathroom, kitchen or utility above the damp shifts the odds heavily towards plumbing.

Is there an overflow pipe running outside? That is a tank or a ballvalve and it needs a plumber.

Did it start after cold weather rather than wet weather? Condensation, or a frozen pipe.

If It Is Plumbing

Turn off the water at the stopcock - usually under the kitchen sink or where the main enters the house - and open the taps to drain the system down. That stops it while you find a plumber.

If it is a cold water tank in the loft, the stopcock will not stop it immediately because the tank still has to empty. Tie up the ballvalve arm or turn off the valve feeding the tank if there is one, and let the taps run.

We are roofers and we will tell you plainly when what you have is not a roof problem. It happens regularly and it is a better outcome for you than a scaffold.

The Widnes Note

Two things worth knowing about the housing here.

A great deal of it has a cold water tank in the loft, and tanks and ballvalves of a certain age fail. If clean water is coming through a ceiling with no rain, that is the first place to look.

And the estates here have roofs now fifty to seventy years old, so genuine roof leaks are common enough that people assume that first. Ruling out the other five takes five minutes and occasionally saves a great deal of money.

Whichever it turns out to be, deal with the electrics first.