My Copper Pipes Keep Getting Pinhole Leaks

A pinhole leak in copper is a tiny hole eaten through the pipe wall from the inside or the outside, and it sprays a fine stream into a wall or a crawlspace until someone notices the stain or the bill. The first one is a nuisance. The second one in a different place is a pattern. By the third, you're paying for locates and patches on a system that is going to keep doing this, and the question becomes whether to keep patching or replace the supply lines once.

Copper pinholes for a few reasons on the Kitsap Peninsula. Water chemistry: some of the county's well and surface sources are slightly acidic or low in minerals, which lets water slowly dissolve copper from the inside. Contact: copper touching concrete, aggressive fill, a steel hanger or a nail plate corrodes at the contact point. Velocity: undersized hot lines with a recirculation pump erode at the elbows. And age: 1960s and 70s copper has simply been in service a long time. Homes in Tracyton, Enetai, East Port Orchard and the older parts of Silverdale and Bremerton are the usual callers.

We repair the pinhole at a located spot with our licensed plumbers, and we look at the pipe on either side of it. Green-blue staining along the run, multiple patches already on the line, or a pinhole with others forming nearby means the system is at the end of its life, and we'll say so. A repipe in PEX-A ends the pattern, and if the exterior service line is the same vintage it gets replaced in the same project.

What it usually means

What to check first

1. Count the pinhole repairs the house has had and where.
2. Look at exposed copper in the crawlspace for green-blue staining or earlier patches.
3. Do the meter test to catch the current leak if there is one.
4. Note whether the pinholes are all on the hot side.

When to call

• This is the second or third pinhole
• Exposed copper shows staining or earlier patches
• The current leak needs locating
• You want a straight answer on repair versus repipe