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What You Need to Know About Pinhole Leaks


Hidden leaks in pipes are a major problem for many homes, often without anyone in the home knowing about them … because they’re, well, hidden

The most common types of hidden leaks are known as pinhole leaks. They’re as small as their name, but that doesn’t mean they can’t cause a large amount of water waste and building damage. Because they’re difficult to notice, pinhole leaks often get ample time to create problems.

In this post, we’re going to provide you with important information about pinhole leaks. This will help you understand why they’re serious and need fast action from professional plumbers to eliminate.

What is a pinhole leak?

A pinhole leak doesn’t just refer to the size of the leak in a pipe, but a leak caused by a specific type of corrosion that occurs in copper. Copper is corrosion-resistant, but that doesn’t mean it’s impervious to all kinds of corrosion. The corrosion that leads to pinhole leaks is known as formicary corrosion or pitting corrosion, which affects small areas of copper piping. The exact cause of formicary corrosion isn’t fully understood, but it’s likely connected to chemicals that can be found in both water and air and high acidity levels within water. 

The weakening of copper due to formicary corrosion creates tiny pits that can soon turn into leaks. These leaks are usually less than ⅛ of an inch wide, but they usually occur in clusters along the corroded area. Pinhole leaks aren’t limited to older piping: they can begin appearing in copper pipes after only two years. 

The pinhole leak problem

Pinhole leaks are both a problem on their own and a sign of larger corrosion problems in the piping. If you can find one area of corrosion with pinhole leaks, then there are likely others. This is why we strongly recommend having leak detection done for your house if you discover any evidence of leaks. Chemicals and pH levels in your water might be creating extensive damage elsewhere. 

How to notice pinhole leaks

This is the big dilemma: how can you know you have pinhole leaks if they’re so good at remaining undetected for so long? You can watch for several signs that will warn you of pinhole leaks:

  • Your water bills are much higher than normal. If there are enough pinhole leaks, they can make a significant difference in water usage.
  • You find mold and mildew growth in unusual spots in your house. Pooling water from pinhole leaks creates an ideal environment for these growths. 
  • You can hear dripping water sounds in your house but can’t find the source. 
  • The water pressure has dropped throughout the house. 
  • There are discolored spots on the walls or ceiling, warning of water damage from leaking pipes. 

If you have any doubts about water leaks, please call our plumbers to arrange for leak detection. If you can have leaks detected and repaired early, you can avoid a future need to call for an emergency plumber in Montpelier, VT.

Red Rock Mechanical, LLC serves Northwest Vermont and Northeast New York. Schedule plumbing service with us today.

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