I just moved into a new house with leaking tiled shower. Tile grout is cracked around shower floor perimeter and curb edges. There are signs of leak visible in basement ceiling, just below the curb.

I started with removing top and outside curb tiles, here is what I found:
1) Bathroom side had two layers of gypsum board screwed to curb, both boards were totally wet and easily disintegrating
2) Top side had one layer of gypsum board, screwed to wood structure of curb, screws going through membrane, gypsum totally wet.
3) There is large gap between shower side of curb tiles and the curb. It appears to me that there was also a gypsum board between tiles and membrane.
3) Membrane ends about 1" from top on outside of the curb, here it is attached to 2x4s
4) Curb wood structure (2x4??) is all wet and black in color

Here are my questions:
1) Should I totally remove the curb and start all over again, how?, or
2) Work with what I have and build around present curb structure using wire mesh and mortar?, or
3) There is other better method.


Please help

#1, except I would add that you will most likely have to demo the rest of the shower as well. Sounds like it was built by someone who didn't know what they were doing. Any attempts to fix the curb alone will be a bandaid fix that won't last.

No, wait.....

You will definitely have to demo the rest of the shower as well.

Kevin's right, rip it all out and start over. Check back here with recommendations on how to build a shower.

Jaz

Better late than... yes definatly demo the entie shower, if your curb had 2 layers of sheetrock over than the person or persons installing the wall tile did not know know what they were doing, who knows whats behind the walls. You cannot penetrate any waterproofing membrane with fastners at all in the shower pan and or curb area ever!!!!! and at least 2" above curb areas.

Sad news. So many showers get build this way.

A lot of traditional liners designed for use with a clamping drain come with only a one year warranty. The only supplier I know allowing drywall for shower curbs is Schluter and this is a horrible idea.

Curbs should in my opinion be made from bricks or cement. Not wood and if wood is used it should be dried stock or KD.

Once a plumber has installed a waterproof shower & curb - the boarders come in. Maybe a couple screws fall, maybe the drill. Then there is the ladders, two steps and stilts from the tapers.

Then the tile guy comes in. Perhaps a few roofing nails to keep the lath in place.

By now the average shower pan has 1-8 holes in it. Odds are there is no pre-slope. The shower after a few months of use is saturated with water. This water wicks through the mortar bed and finds the holes. Then the wood swells causing cracking and failing tile. Then more water gets in quicker. Causing more swelling and faster break down.....

Insure the next shower has no drywall in it. Floors, curbs or walls.

Flood test the next project and tell the boarders you will flood test when their done as well.

Good Luck.

JW