Pan liner on plywood. Possible to repair?

[Steve.]

Hello,
I'm a long time reader, first time poster. I've learned a lot here and want to say how much I appreciate it.

My daughter just moved into a house and discovered a leak at the drain of a tiled shower. The drain appears to be a single piece or a drain that took a tail nut as for a fiberglass pan. The drain threads were set directly in a mud bed about 1" thick. There's a PVC liner under the mud bed on top of the plywood subfloor, it's been cut out to clear the drain. From below I can see its attached to a wall. Water is getting into the mud bed and running along the liner and exiting at the cutout around the drain. Access from below is mediocre, there's a hole in the plywood about 4 3/4" in diameter and the mud bed and liner extend towards the center of this opening about an inch.

Is there any hope of installing a drain and sealing it to the liner or will this require a tear out?

 

[hj]

Tear out. Some shoemaker installed that shower. The liner goes on TOP of the "mud bed" and is clamped TO THE Shower drain so there is NO OPENING around the drain.

 

[Sponsor]

 

[mlofaro7]

I am working with Steve on the project. Here are a few images before he took the drain out.

 

[Jadnashua]

Plumbing code requires the waterproofing layer to be sloped to the drain. The tile is NOT the waterproofing layer. This requires (when doing a conventional shower) a preslope, the liner, a setting bed, then the tile. Most places also require a flood test of the liner prior to finishing things up. There's no way that would hold water!

There's no approved, reliable way to fix what you have without tearing it out. The liner must also go over the curb, extend at least 2" above the top of the curb, and have no holes below that point.

There are IMHO, better ways to build a shower than the conventional method, but that will work if it is done properly.

I've put some stuff in the tutorial section that might give you some background.

 

[Steve.]

OK thanks guys. We figured this was the case but you gotta ask....