A burst pipe is usually caused by material fatigue and corrosion in old metal pipes, by frost in uninsulated lines, by excessive water pressure or by mechanical damage, e.g. drilling into a wall. Both drinking-water pipes and heating pipes can be affected. Consequences range from a damp wall to soaked floors to water running through the ceiling into the floor below.
The first signs are often damp or discoloured patches on walls and ceilings, a rushing sound in the wall, inexplicably high water consumption or a pressure drop in the heating. In an acute burst: immediately close the main stopcock and switch off the power in affected areas. Then call an emergency plumber. For an insured escape-of-water claim, also inform the building or household insurer.
The specialist first locates the leak. For concealed pipes, leak-detection equipment is used – moisture measurement, thermography or acoustic location – so that walls are only opened where necessary. The damaged spot is then exposed, the pipe repaired or the affected section replaced, the system pressure-tested for tightness, and the area dried. For larger damage, technical structural drying follows over days to weeks.
Costs are hard to generalise. An emergency call-out often starts with a call-out and emergency fee of around CHF 150 to 250, plus an hourly rate of about CHF 90 to 140, with a surcharge outside business hours. A simple, easily accessible repair may cost a few hundred francs, but opening walls, leak detection and structural drying can push the total to several thousand francs (guide values, no guarantee). The water damage itself is often covered by insurance.
What to watch for: don't wait if you suspect a leak – shut off the water and document it (photos for the insurer). Wet building fabric must be dried professionally, otherwise mould and follow-on damage threaten. Prevention includes insulating frost-prone pipes, a pressure reducer where mains pressure is too high, and timely replacement of old, corroded pipes.