Pinhole leaks in copper pipes come from corrosion working through the pipe wall from the inside, usually driven by water chemistry, high water speed, sediment, or simply age. A single pinhole can be cut out and repaired. Several pinholes in the same run mean the pipe is wearing thin and more leaks are likely, which is when repiping makes sense. Found a drip or a wet stain? Call (413) 603-1274.
Common causes
- Water chemistry: the pH and minerals in the water can slowly attack copper
- Fast flow: high velocity wears the inside of elbows and tees
- Sediment: grit settling in a low spot causes local corrosion
- Bad joints: leftover flux from soldering can eat through near fittings
- Age: thin-wall copper in older homes has had decades to wear
Why they cause big damage
A pinhole sprays a fine stream or drips slowly inside a wall or ceiling, often for weeks before anyone notices. By the time a stain shows, the framing, insulation and drywall may be soaked and mold may have started. See signs of a leak in the wall and leak detection.
Repair or repipe?
| Repair the spot | Think about repiping |
|---|---|
| First leak in that run | Second or third leak in a year |
| Pipe looks sound around it | Green crust or thin spots nearby |
| Easy to reach | Leaks keep turning up in finished walls |
See repiping in Chicopee. Insurance usually covers sudden damage from a leak, but may not pay to replace worn pipe.
How to find a pinhole leak
Pinholes are often so small you cannot see them. Signs include a water bill that creeps up, the meter moving with everything off, a damp spot on a basement ceiling, a hissing sound in a wall, or green spotting on a pipe. In the basement, run a dry paper towel along exposed copper. A pinhole wets it in one spot. Inside walls, moisture readings and listening devices help find the source before walls are opened.
Pinholes and water damage
Because pinhole leaks often run for weeks unnoticed, the damage behind the wall can include soaked insulation, mold and rotted wood. Once the leak is found, the area needs to be opened, dried and checked, not just the pipe repaired. See leak detection and structural drying.
Water chemistry questions
If pinholes keep appearing across the house, the water itself may be part of the cause. Public water systems test and treat their water, and the Chicopee Water Department can answer questions about the water supplied to your home. Private wells are different and should be tested. A plumber who sees a pattern of pinholes can tell you whether the pattern points to the water, the way the pipes were installed, or simply age.
A temporary fix while you wait
A pipe repair clamp with a rubber pad, tightened over a pinhole, can stop the drip until the section is replaced. Shut the water off first, dry the pipe, and center the clamp over the hole.
Questions
Can I fix a pinhole with a clamp or epoxy?
As a short-term stopgap only. The pipe around it is often thin too.
Is a pinhole leak an emergency?
If water is spraying or a ceiling is stained, shut the water off and call. Small drips still need prompt repair.
Leak in copper pipe? Call now
Call (413) 603-1274 now. Pipe repair and drying in one call, locally owned in Chicopee.