Prevent Leaks With Pipe Dope

Updated: Apr. 26, 2023

Pipe dope plus Teflon tape prevents leaks in water pipes

pipe thread sealantFamily Handyman
A master plumber shares his simple secret to prevent leaks: back up pipe joints wrapped with Teflon tape by dabbing them with pipe dope.

You might also like: TBD

Add pipe dope to prevent leaks

Add a dab of pipe dope

Grab a brush full of pipe thread sealant and wipe it right on top of the Teflon tape. Then assemble the fittings.

Wrapping Teflon tape around pipe threads to create a seal is standard procedure for DIYers. But it’s not foolproof. Burrs inside the female fitting can catch the tape and roll it around. The leak will only show up after you’ve finished the job and turned on the water. At that point, you’ll have a mess on your hands, cutting and refitting pipes.

Here’s a tip from master plumber Les Zell. Go ahead and wrap Teflon tape around the male threads just like always. Then add pipe thread sealant as shown. The pipe thread sealant will fill any gaps caused by tape failures. It’s cheap insurance against a leak. Les says he’s never had a leak since he started adding this second step.

Required Materials for this pipe thread sealant Project

Avoid last-minute shopping trips by having all your materials ready ahead of time. Here’s a list.

  • Pipe thread sealant (pipe dope)
  • Teflon tape