FHB Logo Facebook LinkedIn Email Pinterest Twitter Instagram Tiktok YouTube Plus Icon Close Icon Navigation Search Icon Navigation Search Icon Arrow Down Icon Video Guide Icon Article Guide Icon Modal Close Icon Guide Search Icon Skip to content
Subscribe
Log In
  • How-To
  • Design
  • Tools & Materials
  • Videos
  • Blogs
  • Forum
  • Magazine
  • Members
  • FHB House
  • Podcast
Log In

Discussion Forum

Discussion Forum

teflon tape vs. teflon paste

ahneedhelp | Posted in General Discussion on June 11, 2002 05:20am

Hello –

I am pre-assembling a combination of backflow prevention valve and a ball valve as a main shutoff for the house.
Both valves have 3/4 threaded female ends that will receive threaded 3/4″ male transitions for the 3/4″ copper pipes.
The entire assembly will be connected to the incoming citywater line and then onto the house supply line using compression fittings to avoid soldering problems with wet pipes.
My question is with the 3/4″ threaded fittings – is teflon tape wrapped around several times not good enough these days ?
I recall some comments about favoring the teflon paste instead.

Although the whole assembly could be easily removed I would rather not have to do that.
Which is more commonly used these days ? Paste or tape ?

Thanks for your help,

Alan

Reply

Replies

  1. junkhound | Jun 11, 2002 05:30am | #1

    Paste is almost a must where there are any tiny orifices in the system, such as nat. gas, etc. or rotating parts such as high pressure hydraulics.

    No problems with the tape for water, compressed air, etc where if a little piece of teflon tape from assembly gets in the sytem, worse you'll ever have to do it take a tiny piece out of a faucet aereator or spray gun.

    1. ahneedhelp | Jun 11, 2002 06:09am | #2

      Thanks, Junkhound.

      I was more concerned with ability to maintain a seal.

      If there is no difference between the two, I would rater wrap the teflon tape as it is a lot neater then messing with the paste stuff.

      I did have to use gas rated paste recently for a gas range installation.

      Thanks again for replying.

      Alan

  2. KCPLG | Jun 11, 2002 06:20am | #3

    Teflon tape with a skim of paste to lubricate the threads so the tape stays in place better, and you'll never have a leak. Old plumbers trick.



    Edited 6/10/2002 11:20:54 PM ET by KC

    1. joeh | Jun 11, 2002 08:10am | #4

      And find the thick tape, the pink brand is great. Joe H

      1. UncleDunc | Jun 11, 2002 10:19am | #5

        And don't use too much. Twice around is plenty.

        1. joeh | Jun 11, 2002 05:40pm | #6

          Uncle Dunc, what if he has Chinese parts? Takes about 5 or 6 wraps to make that junk seal. Joe H

          1. UncleDunc | Jun 11, 2002 06:23pm | #7

            I defer to your expertise. It sounds like you earned it the hard way.

          2. NormKerr | Jun 11, 2002 06:59pm | #8

            definitely we all agree,

            use both (tape + paste).

          3. Wet_Head | Jun 11, 2002 08:06pm | #9

            Worthless crap ain't it!

          4. JamesDuHamel | Jun 12, 2002 03:36am | #10

            Wet,

            I assume you mean the Chinese junk.

            Personally, I use a pipe dope in stick form. I never touch it with my hands, and have never had a leak.

            Just a thought...

            James DuHamel

            J & M Home Maintenance Service

          5. User avater
            larryscabnuts | Jun 12, 2002 08:20am | #11

            I second the stick.. I get mine at True Value Harware stores.. I prefer the old paste over teflon. If the threads are wet when you put it on you may have problems..

  3. kbmunkholm | Jun 12, 2002 09:03am | #12

    Something to keep in mind is that teflon tape or paste are not for sealing threaded joints. They are a lubricant only.

    The purpose of the lubricant is to allow the male thread  to be tightened fully into the socket without galling.

    There are products that are available for sealing; John Crane plastic lead seal has lead in it. In BC Canada, this product is approved for natural gas, but not propane.

    Leak lock is a blue substance that hardens that is used for threaded refrigerant connections.

    The old ammonia systems used a mixture of Litharge (which I think is Red Lead) and glycerine.

    When I did service work on gas, I would use two wraps of yellow (thick) teflon and then go over the threads with a stick teflon. Never had any leaks.

    KM

    1. DavidThomas | Jun 12, 2002 11:01am | #13

      I've always liked teflon tape and teflon dope unless there is some super-critical orifice downstream then I use dope only. Guess I gotta find a stick of dope and give that a try now. Don't use Chinese fittings nor Chinese pipe wrenches. Life is too short to chase pinhole leaks, skin knuckles, and worry about political prisoner labor abuses.

      David Thomas   Overlooking Cook Inlet in Kenai, Alaska

  4. GALIVANT | Jun 12, 2002 02:13pm | #14

    Hey guys this is my first time at this site. Just wanted to add a couple more things I've learned about sealing tapered pipe. Whenever I connect new pipe, one or the other usually is fine. But when connecting new pipe to old pipe, it always seems to drip if I don't use both, especially as was pointed out about cheap pipe,(which seems to be more common these days), also since I've never had much luck w/ strap wrench's, I like to use plenty of both on shower head necks & tub spouts. I can tighten to the desired position by hand & I've never had one leak........ Look forward to future chat !!

Log in or create an account to post a comment.

Sign up Log in

Become a member and get full access to FineHomebuilding.com

Video Shorts

Categories

  • Business
  • Code Questions
  • Construction Techniques
  • Energy, Heating & Insulation
  • General Discussion
  • Help/Work Wanted
  • Photo Gallery
  • Reader Classified
  • Tools for Home Building

Discussion Forum

Recent Posts and Replies

  • |
  • |
  • |
  • |
  • |
  • |
View More Create Post

Up Next

Video Shorts

Featured Story

Exterior Materials for a Midcentury Home

Travis talks with the architect about his thought process for choosing the materials that create a functional and seamless aesthetic for this house.

Featured Video

A Modern California Home Wrapped in Rockwool Insulation for Energy Efficiency and Fire Resistance

The designer and builder of the 2018 Fine Homebuilding House detail why they chose mineral-wool batts and high-density boards for all of their insulation needs.

Related Stories

  • Control Layers for a Remodel
  • Superstable Sawhorse
  • Convert a Porch to a Mudroom
  • Podcast 599: Trees Moving Buildings, Epic Thermal Bypasses, and Supplemental Dehumidification

Highlights

Fine Homebuilding All Access
Fine Homebuilding Podcast
Tool Tech
Plus, get an extra 20% off with code GIFT20

"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.

Get home building tips, offers, and expert advice in your inbox

Signing you up...

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
See all newsletters
See all newsletters

BOOKS, DVDs, & MERCH

Shop the Store
  • 2022 Fine Homebuilding Archive
    Buy Now
  • Code Check Complete 3rd Edition
    Buy Now
  • 2023 Tool Guide
    Buy Now
  • Pretty Good House
    Buy Now
  • Shop the Store

Fine Homebuilding Magazine

  • Issue 318 - October 2023
    • Make Mudsills Square and Level
    • Turn Up the Heat With Induction Cooktops
    • The Fine Homebuilding Interview: Lloyd Alter
  • Issue 317 - Aug/Sept 2023
    • Finishing Drywall With Seamless Results
    • A Flat Roof in a Cold Climate
    • Compact Cordless Shop Vacs
  • Issue 316 - July 2023
    • Timber-Framed Solar Canopies
    • Build a Transom Above a Stock Door
    • Understanding Toilet Design and Efficiency
  • Issue 315 - June 2023
    • How to Craft a Copper Roof
    • 5 Lessons from Building in a Cold Climate
    • The Advantages of Cellular PVC Siding
  • Issue 314 - April/May 2023
    • 7 Options for Countertops
    • Tool Test: Wood-Boring Bits
    • Critical Details for Ductless Heat Pumps

Fine Homebuilding

Follow

  • YouTube
  • instagram
  • facebook
  • pinterest
  • Tiktok
  • twitter

Newsletter

Get home building tips, offers, and expert advice in your inbox

Signing you up...

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
See all newsletters
See all newsletters

Membership & Magazine

  • Online Archive
  • Start Free Trial
  • Magazine Subscription
  • Magazine Renewal
  • Gift a Subscription
  • Customer Support
  • Privacy Preferences

Taunton Network

  • Green Building Advisor
  • Fine Woodworking
  • Fine Gardening
  • Threads
  • About
  • Contact
  • Advertise
  • Careers
  • Copyright
  • Terms of Use
  • Site Map
  • Do not sell or share my information
  • Privacy Policy
  • Accessibility
  • California Privacy Rights

© 2023 The Taunton Press, Inc. All rights reserved.

X
X
This is a dialog window which overlays the main content of the page. The modal window is a 'site map' of the most critical areas of the site. Pressing the Escape (ESC) button will close the modal and bring you back to where you were on the page.

Main Menu

  • How-To
  • Design
  • Tools & Materials
  • Video
  • Blogs
  • Forum
  • Reader Projects
  • Magazine
  • Members
  • FHB House

Podcasts

  • FHB Podcast
  • ProTalk

Webinars

  • Upcoming and On-Demand

Podcasts

  • FHB Podcast
  • ProTalk

Webinars

  • Upcoming and On-Demand

Popular Topics

  • Kitchens
  • Business
  • Bedrooms
  • Roofs
  • Architecture and Design
  • Green Building
  • Decks
  • Framing
  • Safety
  • Remodeling
  • Bathrooms
  • Windows
  • Tilework
  • Ceilings
  • HVAC

Magazine

  • Current Issue
  • Past Issues
  • Magazine Index
  • Subscribe
  • Online Archive
  • Author Guidelines

All Access

  • Member Home
  • Start Free Trial
  • Gift Membership

Shop the Store

  • Books
  • DVDs
  • Taunton Workshops

More

  • FHB Ambassadors
  • Reader Projects
  • Podcast
  • FHB House
  • Customer Support

Account

  • Log In
  • Join

Newsletter

Get home building tips, offers, and expert advice in your inbox

Signing you up...

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
See all newsletters
See all newsletters

Follow

  • YouTube
  • instagram
  • facebook
  • pinterest
  • Tiktok
  • twitter

Join All Access

Become a member and get instant access to thousands of videos, how-tos, tool reviews, and design features.

Start Your Free Trial

Subscribe

FHB Magazine

Start your subscription today and save up to 70%

Subscribe

We hope you’ve enjoyed your free articles. To keep reading, become a member today.

Get complete site access to expert advice, how-to videos, Code Check, and more, plus the print magazine.

Start your FREE trial

Already a member? Log in