Hearing Water Running Inside the Wall With All Taps Closed: How to Stop a Hidden Leak
At night when the apartment is quiet, you walk into the bathroom or kitchen and hear a constant hissing sound ('shhhhh') behind the tiles—as if a tap were running—even though every tap in the house is closed. Or you notice paint bubbling and dark damp patches on the hallway wall. You have an active concealed pipe leak.
The 30-Second Test: Is the Burst Pipe Yours or the Building's?
1. Close your apartment's main water stopcock completely.
2. Listen to the wall again: if the hissing stops immediately, the leak is on your private pipework after your meter. Keep the stopcock closed. If the sound continues unchanged, the leak is on the communal rising main or a neighbour's pipe.
Pinpointing the Leak With Acoustic Geophones & Thermal Cameras
Our 24/7 emergency plumbers in Barcelona, Vic, Sabadell, Terrassa and Girona use acoustic geophones and infrared thermography to locate the exact spot behind the wall, opening only 1 or 2 tiles to repair the pipe cleanly. Call 936 94 00 23.
FAQ
What if I only hear water inside the wall when the upstairs neighbour flushes?
Then it is not a pressurized supply pipe, but a cracked PVC joint on the communal wastewater drain stack (bajante).