[rnln]

Originally Posted by trekkor

Do you have access under the house to see if there is water damage?
No, my house is right on concrete.

Block the drain again and add water until it is about half way up the curb.
This is a flood test and will completely saturate the mortar bed.
Make a small reference mark on the wall to keep track of water height.
Let it set for 24 hours before you drain it.
I did this. I poured water to above the crack line, and let it sit for well 2 days. Do you want me to do it again?

Once the water sheds off the tile, you should clearly see water running out from all three weep holes below grade.
I have hard time understanding this part. What is the weep holes?

I suspect one or both of these things is happening:

1. the weep holes are blocked.
2. There is no pre-slope under the water proof membrane.
( should be 1/4 inch per foot to the drain from the farthest corner )

Either of these conditions will cause the mortar bed to become a haven from mold and bacteria, etc.

Report back after the flood test!

Also, how old is the installation? 25-30 years?
I have no idea how old the shower is. The other showers don't look that bad. We have not touched this particular shower for over a year.

KT

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