What Causes a Pinhole Leak
A pinhole leak is a small perforation in copper pipe, usually caused by pitting corrosion on the interior pipe wall. Over years, mineral deposits, water chemistry, and uneven water flow can wear through a tiny section of copper from the inside out, eventually breaking through and releasing a fine spray or steady drip. Read more about our team and certifications if you want to know who will be showing up at your door. If a situation like this is happening right now, you can request emergency service and we'll get moving.
Why Phoenix Homes See More of Them
Phoenix's water supply carries mineral content that varies by neighborhood and municipal source, and homes built between the 1970s and 1990s frequently used copper piping that is now well into the age range where pitting corrosion becomes more common. Combine that with high water pressure in some pressure zones and the result is a metro area where pinhole leaks show up regularly in older residential plumbing. If you want to go deeper on this, our guide on The Complete Water Damage Restoration Process Explained Step by Step covers it well. We also break this down further in What to Do in the First Hour After Water Damage in Phoenix.
Why They're Easy to Miss
A pinhole leak inside a wall cavity often produces only a small, steady dampness rather than an obvious flood, and it can run for weeks before it's noticed. Because the water volume is low, many pinhole leaks are first discovered through a water bill that's higher than usual, a musty smell, or a soft spot in drywall — not through visible standing water. For background from an independent source, see the IICRC S500 restoration standard. the Insurance Information Institute's claims overview has useful guidance on this if you want to read further.
What Happens After One Is Found
Once a pinhole leak is located, the fix usually involves cutting out the damaged pipe section and replacing it with new copper or PEX, plus drying out any wall cavity or subfloor the water reached. If pitting corrosion is showing up in one section of pipe, it's worth asking whether nearby sections of similarly aged copper are at risk too — repeated pinhole leaks are often a sign the whole system is due for evaluation. Our pipe leak water damage restoration team handles both the water extraction and the structural drying that follows. You can also review FEMA's National Flood Insurance Program for an outside perspective on this.