Drain Overflow...Tub to Shower Conversion

Discussion in 'Shower & Bathtub Forum & Blog' started by Cobra1365, Mar 4, 2021.

  1. Cobra1365

    Cobra1365 Member

    Joined:
    Feb 7, 2011
    Location:
    Delaware
    I know I have to go to a 2” drain to be in code. But, can I just cap off the existing overflow tube?
     
  2. Tuttles Revenge

    Tuttles Revenge In the Trades

    Joined:
    Oct 15, 2014
    If you're removing a tub and installing a shower, the Waste and Overflow contraption that is attached to the tub all goes away. Your new shower drain is a completely different animal than the tub drain and will need to have a waterproof membrane or shower pan installed.
     
  3. Sponsor

    Sponsor Paid Advertisement

     
  4. Cobra1365

    Cobra1365 Member

    Joined:
    Feb 7, 2011
    Location:
    Delaware
    That’s sort of what I was thinking. Just wasn’t sure.

    I’m installing a prefab shower pan.

    Thanks!
     
    Tuttles Revenge likes this.
  5. Cobra1365

    Cobra1365 Member

    Joined:
    Feb 7, 2011
    Location:
    Delaware
    Next question.

    The existing tub had a 1 1/2 drain line all the way to the main drain line of the house (4”).

    The video below shows how it was plumbed.

    Since the new shower requires a 2” drain, how do/Can I transition to the 1 1/2 inch line?

    My thought was to cut the existing 1 1/2” line as close to the 4” line as I can and install a reducing coupler for the last few inches before it goes into the 4” line. But, will that cause too much of a restriction to the flow?

    Am I over thinking this or do I need to totally rework where it joins the main line?

     
  6. Tuttles Revenge

    Tuttles Revenge In the Trades

    Joined:
    Oct 15, 2014
    If you have access to the main drain, then the answer is simple, cut in a new 2" drain and install 2" all the way to the shower. There is zero downside to having a fully sized drain.
     
  7. Cobra1365

    Cobra1365 Member

    Joined:
    Feb 7, 2011
    Location:
    Delaware

    That’s the problem. While I can access it, the way they have it plumbed, there are no sections to cut and splice because of all the connections they have in there (see end of vid). It looks to me like I’d have to replace almost all of those connections.
     
  8. Cobra1365

    Cobra1365 Member

    Joined:
    Feb 7, 2011
    Location:
    Delaware
    Just looked over the Code again. I’m good with 1 1/2” drain. I just need to step down from 2” to 1 1/2” prior to P-trap.
     
  9. Tuttles Revenge

    Tuttles Revenge In the Trades

    Joined:
    Oct 15, 2014
    Must be IPC then? Yes, Install the reducer in the shower drain or on the tail piece dropping to the trap.
     
  10. Kevin P Hanson

    Kevin P Hanson New Member

    Joined:
    May 19, 2021
    Location:
    somewhere
    This from 2021 UPC:

    Footnote #9 of table 702.1 says

    "For a bathtub to shower retrofit, a 1 1/2" (40 mm) trap and trap arm shall be permitted with a maximum shower size of 36 inches (914 mm) in width and 60 inches (1524 mm) in length."
     
    Tuttles Revenge likes this.
  11. Tuttles Revenge

    Tuttles Revenge In the Trades

    Joined:
    Oct 15, 2014
    weird that the square footage of the shower would be the determining factor rather than the GPM output. Probably some code leftover from the stone ages
     
  12. Reach4

    Reach4 Well-Known Member

    Joined:
    Sep 25, 2013
    Location:
    IL
    https://codes.iapmo.org/docs/2024/UPC/2021 UPC TC Meeting Monograph.pdfage 240 of 547 talks about that as a proposed modification for the 2024 UPC.

    Maybe they are thinking that a party-sized shower would use more water.

    [​IMG]
     
    Last edited by a moderator: May 19, 2021
Similar Threads: Drain OverflowTub
Forum Title Date
Shower & Bathtub Forum & Blog Shower Drain Extension Oct 1, 2021
Shower & Bathtub Forum & Blog Newly Installed Slip fit shower drain leaks Sep 30, 2021
Shower & Bathtub Forum & Blog Shower/tub overflow drain + tar Sep 26, 2021
Shower & Bathtub Forum & Blog Moving bathtub drain Sep 21, 2021
Shower & Bathtub Forum & Blog No-Caulk Drain and ABS Sep 19, 2021

Share This Page