Redo Grout Only or is Serious Tile Work Necessary?

[Lovegasoline]

jonchicagoland:

Like others have mentioned, I think your cartridge leak is unrelated to the joint cracks that have developed.

The most likely problem is you have a fair bit of water built up within the pan (clogged weep holes and/or no preslope). What happens is the water level rises beneath the tile until it finds a path outwards. If there's gypsum in the curb, that will suck up the water and spread it to the surroundings pretty quickly. If not, we regularly see fastener penetrations in the liner, and over-zealous trimming of the liner. Both of those would eventually let water through.

Were that the case wouldn't it have manifested already in the previous 12 years?

For "non-invasive" inspection, I use a cheap pinned moisture meter. It's not a perfect solution (ie, I don't have numbers that will give you a diagnosis), but it will give you clues to where moisture has gathered. Press the pins pretty hard into the grout joints (the pins will get bent on the hard grout, but they are replaceable). Choose various points to define the drain path (ie, should be a higher number near the drain), and follow the moisture up the walls.

As an example, if you find moisture in the open grout joint on the outside of the shower door, I think that's pretty good confirmation of what folks here are saying.

I have a moisture meter w/pins (not cheap) but wont holes in the grout compromise the shower stall floor's watertighness?
__________________

[jonchicagoland]

Originally Posted by Paul

Were that the case wouldn't it have manifested already in the previous 12 years?

Sometimes these things show early, sometimes later. I don't have hard data gathered on this, but my intuitive sense is the majority of failed showers I see in my area are 10-15 years old. It really depends on just how the combination of installation problems interact, shower usage patterns, how porous the tile is etc.

Originally Posted by Paul

I have a moisture meter w/pins (not cheap) but wont holes in the grout compromise the shower stall floor's watertighness?

Just to clarify: I'm not advocating putting holes in the grout. The pins just need to "bite" a bit to get a reading in the grout. I'd estimate I use about 15 lbs of pressure for an intact grout joint. If you're testing those open joints, you may not need that sort of pressure.

As far as compromising the grout, understand that the grout and tile will let water through anyway - that's why we're all so interested in how the shower is constructed beneath the tile