(206) 949-5683, Top Rated Plumber, Seattle
Results 1 to 4 of 4

Thread: 3/4 inch or 1/2 inch lines?

  1. #1

    Default 3/4 inch or 1/2 inch lines?

    Hello, I'm remodeling a bathroom and I'm getting ready to run new water lines. I had a friend who was a plumber that told me he would run 3/4 inch lines throughout the bathroom. However, all my new fixtures have 1/2 inch rough in valves. Is there any value to the 3/4 inch lines with 1/2 inch fixtures?? It seems to me that the 3/4 inch is overkill if the water is going to be throttled by the 1/2 inchers... Help!


  2. #2
    Master Plumber Redwood's Avatar
    Join Date
    Dec 2007


    I believe I answered this in another forum... Same answer would apply here as well.

  3. #3
    In the Trades Gary Swart's Avatar
    Join Date
    Sep 2004
    Yakima WA


    Unless you are going to use a fancy shower with multiple heads, I think 1/2" will be plenty. One big drawback to 3/4" for hot water is that it wastes a lot of water flushing the cold out before you get the hot water. Of course, you can always use a recirculating system or a point of use heater, but I don't think you'll need it. I did my bathroom with 3/4" once, and it wasn't long before I repiped it with 1/2".

  4. #4
    DIY scratch-pad engineer leejosepho's Avatar
    Join Date
    Nov 2006
    200 miles south of Little Rock


    I used 3/4" as a main line with reducing tees to branch off with 1/2" to fixtures, individually, so no single fixture could drastically affect the overall flow available.


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts