Step 1 — Turn off the water at the stopcock
Find your internal stopcock (usually under the kitchen sink, in a downstairs WC, or in the utility) and turn it fully clockwise. This stops mains water flowing into the house. If you can't find it or it's seized, your outside stopcock is at the boundary of your property under a small metal cover.
Step 2 — Turn off the heating and hot water
Switch the boiler off at the spur. If you have a cold water tank in the loft feeding hot water, the tank will keep draining through the burst until empty — so opening every hot tap downstairs after isolating the mains helps clear the system faster.
Step 3 — Turn off the electrics if water is near anything electrical
If water is coming through a ceiling near light fittings, switches or sockets, isolate the consumer unit (fuse box) before going near it. Water and 240V do not mix.
Step 4 — Contain the damage
Use buckets, towels and bowls to catch water. If water is bulging a ceiling, carefully pierce the bulge with a screwdriver into a bucket — counter-intuitive, but a controlled drain is much better than a ceiling collapsing.
Step 5 — Photograph everything
Before you start mopping up, take photos and short videos. Your home insurance claim will go much faster with clear before-and-after evidence.
Step 6 — Call an emergency plumber
Once the water is off and contained, call an emergency plumber. A competent plumber can isolate the burst section, repair it and have your water back on the same day in most cases. If you're in the West Midlands, M3 Trades responds to emergency callouts across Birmingham, Solihull, Sutton Coldfield, Dudley, Stourbridge, Coventry, Wolverhampton and Worcester.