Keeping safe first
A stain spreading across a ceiling or a damp patch is not usually dangerous in itself, but water and electrics do not mix, and standing water weakens plaster. Take these points seriously before you do anything else.
If any part of the structure looks at risk of collapse, or there is a fire risk, call 999. That is different from a routine leak, and the two should not be confused.
- Do not touch a wet light switch, fitting or socket, or anywhere near one
- If the consumer unit is dry and reachable safely, you may switch off the affected circuit; otherwise leave it to a qualified electrician
- If the ceiling is bulging or sagging with trapped water, stay out of that room and keep others out too
- Do not poke or puncture a bulging ceiling yourself; the water underneath can be more than expected
- If you can safely position a bucket well away from electrics and any bulge, catching the drip can limit damage; if not, leave it
Is it the roof, a pipe, or condensation?
Water on a ceiling does not always mean a roof leak. A stain appearing or worsening during or after rain points towards the roof. A patch that turns up regardless of weather, especially near a bathroom, kitchen or pipe run, points more towards plumbing: a leaking pipe, a failed shower tray seal or an overflowing appliance. General dampness with no clear source, often worse in cold weather and sometimes with mould can be condensation rather than a leak.
Telling these apart matters, as a roofer, a plumber and better ventilation are three different fixes. Lee can help you think through which it sounds like on the phone, though a physical look is often needed to be sure.
If it might be a pipe
If you suspect a leaking pipe rather than the roof, and the stopcock is dry and easy to reach, turning off the water supply there can limit further damage while you arrange a plumber. If you are unsure where it is, or reaching it would mean standing in water or near electrics, leave it and get help instead. This is not guaranteed to stop the problem if the fault lies elsewhere.
How serious is the leak?
A small, stable stain that has not grown is different from a ceiling that is visibly swelling or actively dripping. The size, how quickly it spreads and whether there are visible cracks or sagging all show how urgent it is. A sudden, fast-growing patch after a storm is a stronger sign of ongoing roof damage than a faint mark that has not changed.
If the damage looks sudden and significant, our emergency roof repairs page covers requesting help and temporary protection for the roof itself.
Roofing repair cost versus indoor repair cost
If the roof is the cause, the roofing repair, whether tiles, flashing or a valley, is priced separately from fixing the ceiling itself. The roofing side depends on what has failed, access, and whether timbers underneath need attention. Once the source is stopped, the ceiling plaster, damaged insulation and redecoration are a separate job, usually carried out by a plasterer or decorator, priced on the extent and size of the area affected. A leak that looks small on the ceiling can still mean a larger roofing repair above it, or the other way round.
Drying and making good after the source is fixed
Stopping the water and repairing the room are separate stages. Before painting, the affected plaster, insulation and surrounding timber need assessment and sufficient drying. Covering a damp stain can hide ongoing moisture rather than resolve it. A damaged ceiling may need replacement or repair, with electrical fittings checked by a qualified electrician before normal use resumes. Record where water appeared and retain photographs and repair paperwork, but do not disturb a weakened ceiling to collect evidence.
Need it sorted? Book a roof repair
If you think the water is from the roof, book a roof repair or use our quote form and describe what you can see and when it appears.
For tracing an active leak, see roof leaking, and if tile damage outside looks obvious, our slipped and missing roof tiles page covers that separately.