A pinhole leak is a very small hole that forms in a copper water pipe as the metal slowly wears away from the inside or outside. The hole may be no bigger than the tip of a pin, but it can spray or drip water steadily and cause damage over time.
What Causes Pinhole Leaks
Copper is a long-lasting material, but it is not perfect. Several things can wear it down:
- Water chemistry: water that is slightly acidic or high in certain minerals can eat at copper.
- High water speed: fast-moving water, especially at bends, can wear thin spots.
- Sediment: grit in the water can scrape the inside of the pipe.
- Age: older pipes have simply had more time to wear down.
Signs to Watch For
Pinhole leaks often start out of sight. Look for small water stains on ceilings or walls, a damp spot under a pipe, green or blue spots on copper, or the faint sound of hissing. A water bill that rises without a reason can also point to a hidden pinhole. Check exposed copper in the basement first, since it is the easiest to see.
Why They Should Not Wait
A tiny leak can soak drywall, insulation, and wood for weeks before anyone notices. Mold can grow in that damp space. Pinholes can also be a sign that other parts of the same pipe are thin, so another leak may follow.
A clamp can slow a pinhole leak for a short time, but it is not a lasting fix. The weak section usually needs to be cut out and replaced. If you see more than one pinhole leak, a plumber may suggest checking a larger section of piping.
When a pinhole turns into a spray or a split, repairing the damaged copper quickly helps protect walls and floors. For questions about aging copper lines, you can talk to our plumbing team nearby or call JPR Plumbing at (833) 603-1840.