There are only 3 approved methods to repair a copper water pipe under the foundation of a home.

Those methods are:

• Copper Weld Repair
• Re Route
• Re Pipe

There is no other State Approved Repair Possible.

Every Pipe Repair you See On This Page Has Been Done Wrong

I pulled these from websites from Southern California plumbers and a DIY website. There is no clamp or compression coupling of any type that is approved for under concrete water repairs for temporary or permanent repair. None whatsoever. These are examples of actual secondary leaks from those repairs and potential leaks from those repairs. This is surefire way to flood your home.

There is No Short Cut for Proper and Safe Pipe Repair

The simplest method to fix a water leak below the foundation is to open it up and weld it in place with an oxygen acetylene torch and 15% silver bearing solder. The 15% silver bearing solder is an approved brazing compound for fixing water leaks under concrete. It is pliable and melts at a lower temperature than the 5% or 0% brazing compounds on the water. Standard solder, the stuff that you use a flux with, is not approved for under slab work and tends to leak after awhile.

Why Does Standard Solder Tend to Leak on Joints Below the Concrete

It leaks because the tolerances between the old pipe and the new fitting are too loose. The reason that they are too loose it because the pipe had been in the ground vibrating against the soil for years by the time we find and fix the water pipe. It is no longer a smooth polished copper water pipe. The pipe is pitted, scratched and is worn on the outside. The non-silver bearing solder is not capable of acting like filler, while the 15% silver bearing solder is outstanding at filling these gaps in perfection.

Why Not Use 50% Silver Solder?

It is really expensive. Silver is not cheap. The 50% silver bearing solder melts at an even lower temperature but doesn’t have the same filler qualities. It is closer to standard solder. It is approved and is considered brazing. It will work provided that the piping is in good shape.

Can I Use a Propane or Mapp Gas Torch to Braze the Pipe Leak?

Propane isn’t hot enough, but Mapp gas is, but using it is a mistake. The reason that using a regular torch for fixing the slab leak is a mistake is because it uses the oxygen from the surrounding environment for burning. Once your torch goes down into the hole where the pipe is leaking the oxygen is quickly used up and the flame can go out, burn poorly or simply burn cooler. Most Mapp gas torches cannot be used upside down with the tank higher that the tip of the torch. If this happens, liquid can come out of the tip and ignite throwing out 2 foot flames. This can cause serious injury. The oxygen acetylene torch can be used at any angle, burns at 5600 degrees (You need about 1100 on the pipe) and does not use the surrounding oxygen. You are much less likely to have a “cold joint” with a poor sealing connection with this type of torch.

The picture to the right is an example of epoxy water pipe repair. This came out of a home in Newport Beach. Notice how coverage is either too little or too much? This is not alisted repair for under ground water pipe leaks. Putting enough epoxy in a pipe and praying that it will plug a hole is a very foolish way to repair a slab leak.