A leak you can see gets fixed. Someone notices the drip, puts a bowl under it, and calls. The leaks that do real damage are the ones nobody sees for months, and they almost always gave signals first.
The signals are easy to miss because each one has an innocent explanation.
The water bill that crept
Not the bill that doubled — that gets noticed. The one that went up by a bit and stayed up. People attribute it to a rate change, a visitor, a hot month, a new dishwasher.
A useful test: turn off every tap and appliance that uses water, then look at your water meter. If anything is moving, water is going somewhere. It is the single most direct evidence there is, and it takes two minutes.
The sound of water when nothing is running
Stand in a quiet house late at night and listen. A faint hiss, a trickle, a sound like a tap left barely on in another room — that is not the house settling. Water moving through a pipe makes a noise, and a pipe that is losing water makes it continuously.
People habituate to this remarkably fast. If you noticed a sound six months ago and stopped noticing it, that is not evidence it stopped.
A warm patch on the floor
Almost always a hot water line under a slab. A section of floor that is warmer than the floor around it, in a spot with no heating below it, is a hot water leak until proven otherwise. It is one of the clearest signs there is and one of the most commonly ignored, because a warm floor does not feel like a problem.
Musty smell that comes and goes
Damp materials smell. Not dramatically — a faint earthiness in one room, or in a cupboard, or when the heating first comes on. It gets attributed to the age of the house, to the season, to a rug.
Trust your nose in one specific case: if a smell is localised to one area and does not exist elsewhere in the home, something in that area is holding moisture.
Paint or drywall that is doing something subtle
Not a stain — a texture change. Paint that has lost its sheen in a patch. A seam that has hairline-cracked. Baseboard that has cupped slightly away from the wall. Tile grout that is discoloured in one line and nowhere else. Wallpaper lifting at one edge.
Each of these is what drywall does when it has been repeatedly wet and dried. A single event leaves a stain; slow ongoing moisture leaves distortion.
Mould in a place with no obvious water source
Bathroom mould is a ventilation story. Mould in a bedroom corner, inside a closet, behind furniture on an exterior wall — that is a moisture story, and the moisture came from somewhere.
Pressure that dropped and stayed down
If a shower that used to be strong is now merely adequate, and nothing changed, that is worth investigating. A leak upstream of a fixture takes pressure away from it. This one is easy to adapt to — people simply get used to a weaker shower over a year.
What happens next
The reason leak detection is its own job, rather than part of a repair, is that the wet spot is rarely above the leak. Water travels along joists, follows pipe runs, and emerges at the lowest point it can reach — which can be a room away and a floor down. Opening the wall where the stain is often finds dry framing and no pipe.
Finding it properly means narrowing it down before anything gets opened: isolating sections of the system, listening with equipment that hears what you cannot, using thermal differences to see where a hot line runs and where it is losing heat. The goal is to open one small area, once, in the right place.
That is worth more than it sounds. The difference between a located leak and a suspected one is the difference between a patch and a renovation.
If you have noticed one of these
You do not need to have all of them. One clear signal — a moving meter with everything off, a warm patch, a sound at night — is enough to be worth a look.
Call 604-865-7979. We cover Vancouver, Burnaby, Richmond, Coquitlam, Port Coquitlam and New Westminster.
Related: Leak detection and repair · Why finding the leak is the hard part · Water pressure problems
