How to Repair a Pinhole Leak in a Copper Pipe

A system of worn copper piping.
  • 1-2 hours
  • Intermediate
  • 30-50
What You'll Need
Repair clamp
What You'll Need
Repair clamp

Copper pipes are often plagued by pinhole leaks, and while their cause is hotly debated in plumbing circles, how to fix them is not. There are a few different methods, including using a chemical sealant, solder, or replacing the damaged length of pipe using couplings, but the easiest strategy for any DIYer has to be using a repair clamp.

Repair clamps are available in a wide variety of materials and sizes, and they can be found at most every home improvement center or hardware store. This job should take no more than 20 minutes to complete, saving you a call to the plumber and quite a bit of cash.

Step 1 - Measure the Damaged Pipe

As mentioned previously, repair clamps can come in various sizes, so to properly cover a pinhole leak with one, you will need to know the diameter of the pipe. Note this measurement when you have it and take it with you to the store so the clamp you purchase will fit perfectly.

Step 2 - Turn Off the Water

Before you can secure the clamp, you will need to turn the water main off. The clamp will not fit properly if you try to place it over a running leak.

Step 3 - Clean the Pipe

Your repair clamp also cannot create a proper seal if it grips dirt instead of the pipe surface. The copper doesn’t need to sparkle but it should be free from dust and any type of buildup, so use a dry rag to wipe the length of pipe around the leak. If some debris proves stubborn, feel free to use a slightly more abrasive method. Avoid getting too tough, as you could deal damage to the pipe, and make sure to let the area dry afterward if you use water.

Step 4 - Place the Repair Clamp

There will be a flexible metal pad on the inside of the clamp, and the rubber on top should be centered over the pinhole. Open the device and place it in the desired area. Then, simply close it, and use the screws to tighten. You want to make sure that the clamp is tight, as that is what will stop the leak. However, you must take care not to over tighten the clamp because this could actually damage the pipe, causing a break or a larger leak.

Step 5 - Turn the Water Back On

Once you believe the clamp is tight enough, turn the water back on. Inspect the area for several minutes to ascertain whether or not the clamp needs further tightening. If the leak has ceased, your repair was a success and you can congratulate yourself on a simple, cheap fix. If you do have to tighten the clamp, note that you don’t actually need to turn the water back off to do so. Simply turn the screws until the leak stops or until you can't go any further without the pipe incurring damage.

That’s it. With just two materials, you can stop a pinhole leak in your copper pipes. There is no need to call a plumber. Not only do you save money, but you completed a satisfactory repair in less than an hour's time!