How to Fix a Leaky Shower Drain – Part 5

How to Fix a Leaky Shower Drain – correct a failed shower drain repair by taking apart the drain, clean up the excess Plumber’s Putty and install a new drain.

A reader attempted to repair his leaky shower drain as described in Parts 1 to 4 of this project series, but was frustrated because the shower drain kept leaking. He realized that we both live in the Atlanta, GA area – only 30 minutes apart in fact – and asked if I’d help fix the drain or he’d have to call a plumber. I agreed if I could document and publish the repair. So I packed up my tools and camera for a visit.

Shower Drain Leak & Drywall Ceiling Damage

The shower in the master bathroom on the first floor was leaking onto the drywall ceiling of the finished basement. The leak was quite large as seen by the water stains on the ceiling. The homeowner enlarged the hole in the ceiling to gain access to the PVC shower drain plumbing.

Drywall Ceiling Damage Caused by Leaking Shower Drain

This is the shower drain and 2″ PVC P-trap as seen through the ceiling. This was a significant leak that may have gone unnoticed for some time which weakens the drywall and causes it to crumble. It’s best to first cut a small inspection hole, and if you need to enlarge it, try to make square cuts aligned with the wall, working carefully to minimize the damage to the drywall ceiling. A square or rectangular hole that’s aligned with (i.e. parallel to) the wall is easier to cover with an access panel or false air grill for a neat appearance.

Leaky Shower Drain Drywall Ceiling Damage

Leaky Shower Drain Drywall Ceiling Damage

A closeup of the homeowner’s repair reveals that plumber’s putty has squeezed out past the rubber gasket (which forms the watertight seal) between the fiberglass shower pan and shower drain body. The shower drain continued leaking in this condition:

Shower Drain Repair: Too much Plumber's Putty Interferes with Rubber Gasket

Shower Drain Repair: Too much Plumber’s Putty Interferes with Rubber Gasket

We removed the glass doors from the fiberglass shower for easy access to the shower drain.

Fiberglass Shower and Drain

There was a lot of plumber’s putty around the shower drain. Putty that’s above the edge of the drain should be trimmed off and discarded.

Shower Drain and Plumber’s Putty

Shower Drain Inspection & Repair

The first thing to do is disassemble the shower drain, clean everything up and inspect the drain and shower pan for cracks or broken parts. I began by remove the two screws from the strainer and lifting off the strainer:

Leaky Shower Repair: Remove the Shower Drain Strainer

Leaky Shower Repair: Remove the Shower Drain Strainer

The shower drain body was unscrewed by turning it counter-clockwise (“lefty loosey”) and removed.

Leaky Shower Drain Repair: Unscrew and Remove the Shower Drain Body

Leaky Shower Drain Repair: Unscrew and Remove the Shower Drain Body

This repair is continued in How to Fix a Leaky Shower Drain – Part 6.

Thanks for reading,

Bob Jackson

Copyright © 2016   Reproduction strictly prohibited.

7 Responses to How to Fix a Leaky Shower Drain – Part 5

  1. Nerissa February 9, 2011 at 11:18 am #

    Thank you for you series on how to fix a leaky shower drain. Oddly enough this series described my EXACT problem…from part 1 to 7!!! It was like you wrote it just for me! Thank you so much. Because of you and your very detailed instructions I was able to fix our leaky shower (with a pinch of help from my husband), saving us the cost of a plumber. Simple awesome!!! Thank you again!

    • Bob Jackson February 9, 2011 at 12:30 pm #

      You’re welcome! Thanks for letting me know it helped and saved you the cost of a plumber.

  2. Jack June 11, 2016 at 5:17 pm #

    Really interesting tutorial. It helped me find what was wrong with my shower drain.

    I have a question because I don’t know how to fix it.

    The shower is in the basement and the shower drain body is fixed in concrete so it doesn’t move.

    Also the shower pan drain recess is not completely aligned and is not leveled. One there’s a 1/4” space and on the other side there’s no space at all.

    So there was no rubber gasket and it’s not possible to place one so that the drain will be completely sealed. (Nothing moves, so it won’t secure it correctly)

    Can I use silicon caulk instead of the rubber gasket. Otherwise, what can I use ?

    The guy at home depot said it won’t hold and it will melt because it’s suppose to have some surface that touch air and that I have to reinstall completely my shower. I’m sure there’s a way to seal it without reinstall everything.

    Do you have any idea ?

    • Bob Jackson June 11, 2016 at 6:43 pm #

      > shower drain body is fixed in concrete so it doesn’t move
      Do you have a tiled shower pan? If so the drain is set in a cement mortar bed.

      Shower drains for tiled showers have a different configuration compared to drains for a fiberglass shower pan. First it helps to understand how a tiled shower drain is installed. See these projects:
      How to Finish a Basement Bathroom – Part 2 for the installation basics.
      How to Finish a Basement Bathroom – Part 3 which explains the tile shower drain installation in greater detail.

      Also see my reply dated Sept. 12, 2015 to a reader question with a tiled shower drain leak.

      Let me know if the above helps with your situation. If not, we can discuss other solutions.

  3. Jack June 12, 2016 at 2:18 pm #

    Thanks for the answer but it’s a fiberglass shower.

    The drain is glued (I think) to a pipe that comes out a cement mortar bed. So it doesn’t move.

    The fiberglass touch one side of the drain so tight that I can’t place a gasket under, but on the other side there’s like a 1/4” gab between the fiberglass and the drain. If I place the strainer body, it won’t close the gab because nothing moves.

    I try to find something to fill the gab without rebuilding all the shower :(

    • Bob Jackson June 12, 2016 at 4:23 pm #

      I understand the problem now: The fiberglass shower stall drain opening is not aligned with the PVC drain pipe in the basement floor concrete slab. Which means the shower stall was not installed correctly.

      Do you have a one piece fiberglass shower stall? As shown in this How To Install A Fiberglass Shower video the drain alignment is achieved by:
      * the shower drain pipe is set inside a larger diameter recess in the slab floor to allow some side-to-side movement.
      * the shower drain is installed before fastening the fiberglass stall to the rough opening.
      * the shower stall is fastened along the top and side edges to the wall framing with the bottom fixed only by the shower drain and general rigidity of the stall shell.

      Couple of ideas for aligning the shower stall with the pipe stub in the slab floor:
      1 – In the room on the “1/4 inch gap” side shower, cut an opening 10 inches wide and 6 inches high in the drywall near the floor. The size of the opening isn’t critical but large enough to easily put one or two hands through. You should now see the unfinished side of the fiberglass shower stall. Reach in and push the bottom of the shower stall to close that 1/4 inch gap at the drain. Hopefully it won’t take much effort because the fiberglass stall is flexible. Install a new drain gasket and tighten the drain body. This is a two person job to push and install the drain. Close the maintenance opening in the drywall with either a false vent cover or a bauco Access Panel.

      2- If the shower stall won’t budge per idea #1, remove the drain, drill 1/4 inch weakening holes in the slab on the “gap” side about 1/2 inch away from the drain pipe, then chisel out the concrete so it can move a little to close the gap. This will be tedious work but most floor slabs are only 4 inches thick. At this point it’s probably less time and aggravation to tear out the shower stall.

      Let me know what you do.


  4. Jack June 13, 2016 at 8:45 pm #

    It’s more something like this and it’s glued so it won’t move

    I’m thinking of just putting some caulking around the shower drain body and skip the gasket. Water will stay in the shower a little bit but I won’t have to remove all the shower.

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