Soldering is a handy tool when it comes to plumbing repairs. Anyone with a little experience with a propane torch can tell you, however, that soldering is never a one-size-fits-all operation, with different jobs requiring different techniques. In particular, soldering brass pipes can be more challenging than soldering copper.

Read on to learn why this is, and how plumbers solder copper and brass pipes.

Are Copper and Brass the Same?

No. Copper is a pure metal, whereas brass is a copper alloy, a mix of copper and zinc. Having this addition of zinc in brass is what makes it stronger and more ductile.

The Difference Between Soldering Brass vs. Copper Pipes


Unlike copper, solder for brass requires much more heat for the process to work properly. In fact, you may have to heat the metal five or six times as much as copper for it to reach the point where the solder will melt! This may require higher heat from the torch, more time applying heat to the metal, and diligent attention to hitting the pipe with the flame from all directions.


Copper, however, is a softer metal that will require a lower heat level to solder.

Related Content: Learn the Difference Between Soldering and Brazing

Can You Solder Brass to Copper?

Yes. There’s no issue with soldering brass to copper. The only difference to keep in mind when doing so is the heat requirement differences. This same logic can be applied to soldering copper to brass.

How to Solder Brass and Copper Pipes

If you’re soldering water pipes, the basic process for joining brass or copper is essentially the same. Here’s how plumbers do it:

  1. Clean the pipe ends that will be joined until they are shiny and free from any burrs or debris.
  2. Next, brush on the plumbing flux and push the pipes together.
  3. Finally, heat the fitting using a torch, while dripping liquid solder into the joint to create a secure and water-tight barrier.

However, when it comes down to the specifics, there are a few distinctions to consider between soldering brass and copper.

Tips for Soldering a Brass Pipe

Brass pipes are quite uncommon, so usually when we are soldering brass, it means we’re working with a valve. In addition to the general steps listed previously, we follow these steps as well:

  • Make sure the valve is open. Otherwise, the pressure inside can build up from all the heat, which can cause air to escape and create a leak.
  • If the propane torch isn’t hot enough to get the job done, we’ll try MAPP gas. This is a mix of methylacetylene and propadiene that can reach a higher temperature than propane.
  • Apply flux or soldering paste liberally, which etches the pipes and facilitates the process of the actual solder binding the metal together.

Tips for Soldering a Copper Pipe

  • Apply heat for short, quick periods to avoid oxidation on the copper pipe.
  • Don’t add direct heat to the areas already soldered. This could start the flow of that solder again, especially because solder for copper reheats at a lower temperature.
  • While the pipe is still warm, wipe away any leftover solder drips to avoid the copper rusting over time.

Related Content: Basic Copper Pipe Soldering Tips

How to Weld a Copper Pipe

Unlike soldering, which requires melting a filler material to create a bond, welding involves fully melting the base materials together. Welding requires the use of specific, professional techniques. Because of this, we recommend you don’t attempt any type of DIY welding. It could be a danger to your safety and likely result in costly plumbing damage.

Get Expert Help for All Soldering (and Welding) Plumbing Repairs

Though soldering can sometimes be a quick, easy fix, having a plumbing professional do the job (big or small) will guarantee the safety and longevity of your plumbing pipes.

If you need help with any type of soldering job or other bathroom plumbing repairs, contact the licensed plumbers at Benjamin Franklin Plumbing. We guarantee quality that will fix the problem now and provide a long-term solution. Call us at 1-877-BEN-1776, or request an appointment online.