How does a hidden water leak show itself?
A hidden leak often shows first as a change in the water bill, a soft floor, a damp wall or a musty smell. The sign may appear far from the leak, because water runs along pipes, joists and plates before it reaches a surface.
Water that leaks inside a wall or under a floor finds the easiest path. It runs along framing and fills low points, so the stain or the wet spot can be several feet away from the line that is leaking.
A slow leak can run for months without a visible mark. The first sign is often a rise in the water use or a sound at the pipes that does not stop when the taps are closed.
Can a technician find a leak without cutting into the wall?
Often, a technician can narrow the area without cutting, using moisture readings, thermal imaging and the water meter. The final access point is cut only where the readings and the checks point to the source, and only as large as needed.
The meter test and the readings show whether water is leaving the supply, and roughly where. Thermal imaging can show cooler, wet material behind a surface, which helps the technician choose the cut location.
Some leaks need a small opening to be seen directly. The crew explains where the opening will be, why it is needed and how it will be closed, before anything is cut.
What moves the cost of a hidden leak job?
How far the water has travelled, how many surfaces are wet, how many openings are needed and how the line is reached all decide the job. The price is explained and approved before work starts.
A leak that is found quickly inside one wall is a shorter job than one that has wet several rooms and a subfloor. Each opening adds work for the crew and the finish trade that closes it.
The repair of the line is plumbing work, and it is done by a plumber you choose. The water crew's part is the finding, the drying and the record, and the scope explains how each is priced.
Why should a hidden leak be found before the wall is closed?
A wall that is closed over a leak keeps the water against the framing and the drywall until it is discovered again. Finding and repairing the source first, then drying the cavity, avoids repeated damage and repeated repair.
A patch over a wet cavity traps the moisture, and the wood and the drywall are damaged again. The record of the readings and the repair is what tells you the cavity is dry before it is closed.
The plumber should confirm the repair holds before the wall is finished. Ask the technician to show you the readings and let the plumber see the opening before it is closed up.
What should a homeowner do while the leak is being tracked?
Keep the water shut off to the suspected line, avoid running the fixtures on that line, and mark any wet spot you can see. Do not break into walls on your own, and keep a record of the water meter reading each day.
A simple daily reading of the meter, taken at the same time each day with the fixtures shut, shows whether the leak is still running. Write it down and show it to the technician.
If a wall or floor becomes soft or starts to sag, keep people away from that area and tell the technician. Do not use electrical equipment near a wet wall or floor until the power has been checked.
