How to Solder a Pipe | Ask Richard | Ask This Old House

This Old House plumbing and heating expert Richard Trethewey shares tips on soldering pipe. (See below for shopping list, tools, and steps.)

Shopping List for How to Solder a Pipe:
- Lead-free solder
- Flux and acid brush to ensure solder bonds to copper pipe and fittings
- Propane cylinder
- Dry cloth

Tools List for How to Solder a Pipe:
- Safety glasses
- Propane torch with striker to melt solder
- Tubing cutter to cut copper pipe
- Emery cloth or Cleaning brush to clean copper pipe and fittings
- Screw-on torch tip to attach to the propane cylinder
- Heat shield to prevent torch flame from burning combustible surfaces

Steps for How to Solder a Pipe:
1. Use a cleaning strip or an emery cloth to clean the outside of the copper pipe and the inside of the copper fitting.
2. Use an acid brush to apply flux onto the pipe end and inside the fitting.
3. Push the fitting onto the pipe until they fit tightly together.
4. Thread the torch tip onto the propane cylinder, then open the valve and ignite the propane with a striker or a built-in igniter.
5. Adjust the valve to create a sharp, well-defined pencil-tip flame.
6. Use the torch to apply heat to one side of the copper fitting.
7. Once the flux starts to bubble, press the solder against the opposite side of the fitting.
8. Wait for the heat to melt the solder, then and draw the solder into the joint.
9. Remove the flame and gently wipe away any excess solder with a dry cloth.
10. When soldering existing pipes, be sure to drain all water out of the pipes first.
11. Use a fireproof heat shield to protect wood framing, insulation and other combustibles from the torch flame.

About Ask This Old House TV:
Homeowners have a virtual truckload of questions for us on smaller projects, and we're ready to answer. Ask This Old House solves the steady stream of home improvement problems faced by our viewers—and we make house calls! Ask This Old House features some familiar faces from This Old House, including Kevin O'Connor, general contractor Tom Silva, plumbing and heating expert Richard Trethewey, and landscape contractor Roger Cook.

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How to Solder a Pipe | Ask Richard | Ask This Old House

[massinissa]

Concise and precise, beautiful thank you . YouTube needs more like you.

[samanthajennings]

You can heat just the bottom and put solder at top of the fitting and it will pull it through to the bottom on 1/2 fittings

[Steelrailbearing]

This is exactly what i was looking for, fast and straight to the point. I haven't sweat a pipe in 15 years and was looking for a refresher. I now have a new Amtrol tank and no leaks! Thank you!

[gregorygalati]

I've watched a lot of in-depth videos that took a half hour and yet this video was easy and provided all the information in that video did

[devaunramsey]

That smile after seeing sooo much flux lol

[yumann]

You don't want to burn the house.
Pretty good advice.

[sbauman]

And how do you get all of the water out of the old pipe, tricky

[cranjismcbasketball]

Ahhhh don't stick you finger in the flame!!! Haha awesome explanation!

[jinpark]

It seems to me that you apply too much flux and a lot of them will end up inside the pipe.

[nedcramdon]

He doesn't flux around, does he. Mondo flux!

[fldave]

Richard knows better, that's WAY TOO MUCH flux, that's going to erode the copper especially on the cold side over a short time.

[alexyanker]

Thank you wish I saw this before I accidentally burned down the house. Unfortunately my wife didn’t make it out in time but I was able to get my baseball card collection out.

[ninjawriter]

one time I didn't get all the water out of the pipe and the pipe was sealed so it eventually evaporated, turned to steam, exploded from the pressure like some sort of steam bomb, spraying me with liquid solder. Ya, it sucked.

[mikimiki]

How do you make sure all water is out if you working in the basement it constantly drips down

[phxtonash]

If a old pipe is still driping water put a piece of bread in it to stop water, than solder when done the bread will simply spray out faucet

[steven-sljv]

Whats a good way to take out the water to soder and complete the job? Beginning my handyman career and learning as i go any body who did the same please feel free to leave positive comments

[IAmKyleBrown]

One of your best videos! Nice work Richard and team. Thanks!

[websurfer]

More tricky when you have to solder 3 joints quickly, as with a TEE fitting.

[Australia-kykx]

Good info often wondered how its done.

[OffGridInvestor]

That's enough flux to do half the bathroom....