Pan liner penetration

[Rlc52]

Due to failed water filtration in condo above, my kids condo at school was stripped to the studs- including shower pan. As it was an odd size, I could not find a pre-made pan. So I made a custom one. 1 1/2 inch dry packed sand mix sloped to drain, 40 mil PVC liner with corner folded into notches cut out in the studs and edges stapled 7 inches above pre-slope and over shower curb, and then another 1 1/4 inch sloped dry pack sand mix and mortar poured into form made for curb. Turned out really good. I talked to the sheetrock contractor and physically showed him the blue painter's tape I ran around the top of the 40 mil PVC liner and instructed him NOT to place screws to hold the hardboard below the tape as to avoid penetrating the liner. Result-6 screws about an inch from bottom of the hardboard. Before informing me, he removed the screws, squirted in Gorilla glue and replaced the screws. Does Gorilla glue even stick to pvc liner? It would be extremely difficult to start over as I had to cut the 2 inch pvc pipe below grade and its thru a concrete subfloor. Suggestions? I had planed Red guard the walls, but now it may need Kerdi liner extending well onto the floor. Would this work, and if so, how close to the drain should I get as I have read to avoid getting moisture sandwiched between two liners. Also, Red Guard- thumbs up or thumbs down? Other solutions?
Thanks

 

[Jadnashua]

First off, I'd be really pissed, and probably would withhold payment. Technically, the pan now would not pass a plumbing inspection. Code says no penetrations below 3" above the top of the curb. The only valid patch is made with PVC and the PVC cement, not Gorilla glue, and that's liner to patch, not from above.

I can't think of a good way to patch this.

FWIW, the instructions on Hardiebacker and the TCNA guidelines require the bottom edge of the Hardie (a fiber-cement board...other type has different requirements) to be stopped ABOVE the top of the setting bed on the pan, otherwise, the fiber (cellulose) in the board can swell and degrade the board. A little damp on the vertical from the outside is fine...wicking up from a wet mudbed from below is not.

There isn't a good way to marry Kerdi to a conventional drain, but it can be done by using the divot method. That would require probably redoing the center around the existing drain. If you were going to do that, it might be just as easy to replace the drain with the Kerdi one, should you decide to go that route and ignore the existing liner.

Unless you're using a sheet membrane, it is expected that the material above the liner will be damp almost always. If it's made right, any moisture that gets there will weep down the liner and out the drain through the weep holes. But, because it is going to be damp, and a fiber-cement board is VERY thirsty, some will wick up into the board if it's touching the pan. That's what needs to be stopped by proper installation methods. Putting waterproofing on top of it won't prevent wicking from below unless you revert to a surface applied waterproofing method, and that requires a different drain unless you go with a divot (Noble makes them).

While surface applied liquids can waterproof things, I'm not a great fan...it's more involved than just painting on two coats. Especially with Hardie, which requires a primer coat first.

Don't' you just hate it when people you are paying don't follow instructions!

Check out www.johnbridge.com where they specialize only on tiled things.

 

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[Rlc52]

First off, I'd be really pissed, and probably would withhold payment. Technically, the pan now would not pass a plumbing inspection. Code says no penetrations below 3" above the top of the curb. The only valid patch is made with PVC and the PVC cement, not Gorilla glue, and that's liner to patch, not from above.

I can't think of a good way to patch this.

FWIW, the instructions on Hardiebacker and the TCNA guidelines require the bottom edge of the Hardie (a fiber-cement board...other type has different requirements) to be stopped ABOVE the top of the setting bed on the pan, otherwise, the fiber (cellulose) in the board can swell and degrade the board. A little damp on the vertical from the outside is fine...wicking up from a wet mudbed from below is not.

There isn't a good way to marry Kerdi to a conventional drain, but it can be done by using the divot method. That would require probably redoing the center around the existing drain. If you were going to do that, it might be just as easy to replace the drain with the Kerdi one, should you decide to go that route and ignore the existing liner.

Unless you're using a sheet membrane, it is expected that the material above the liner will be damp almost always. If it's made right, any moisture that gets there will weep down the liner and out the drain through the weep holes. But, because it is going to be damp, and a fiber-cement board is VERY thirsty, some will wick up into the board if it's touching the pan. That's what needs to be stopped by proper installation methods. Putting waterproofing on top of it won't prevent wicking from below unless you revert to a surface applied waterproofing method, and that requires a different drain unless you go with a divot (Noble makes them).

While surface applied liquids can waterproof things, I'm not a great fan...it's more involved than just painting on two coats. Especially with Hardie, which requires a primer coat first.

Don't' you just hate it when people you are paying don't follow instructions!

Check out www.johnbridge.com where they specialize only on tiled things.

I have carefully created a 1/4 to 1/2 inch gap between the cement board and the dry-packed shower floor. I am thinking of caulking that space with waterproof caulk/adhesive and then fold a 6" mesh tape at the wall/floor intersection. I would imbed it with Red guard. Should this work? Should I Redguard all, or most of the shower floor. Should I worry about creating a moisture sanwich between the PVC liner and the Redguard? Weepholes are present. Thank you for sharing your knowledge.

 

[wwhitney]

Perhaps I'm a bit late with my suggestion, but it seems to me the proper solution is to remove the finish materials over each hole in the PVC liner, patch the PVC liner with appropriate cement and a piece of liner with sufficiently large overlap, and then reinstall the finish materials properly. If all six penetrations were on one wall, it wouldn't be too bad, but I expect they are more spread out. Also, if 1" overlap isn't enough, you'd havc to remove part of your upper setting bed, which if it's not possible to patch would mean redoing the whole upper setting bed.

Cheers, Wayne

 

[Jadnashua]

I have carefully created a 1/4 to 1/2 inch gap between the cement board and the dry-packed shower floor. I am thinking of caulking that space with waterproof caulk/adhesive and then fold a 6" mesh tape at the wall/floor intersection. I would imbed it with Red guard. Should this work? Should I Redguard all, or most of the shower floor. Should I worry about creating a moisture sanwich between the PVC liner and the Redguard? Weepholes are present. Thank you for sharing your knowledge.

The mudbed will normally be damp in a conventionally built shower with a liner. So, trying to waterproof the walls to protect holes the installer may have put in the liner below the designated height above the curb is just trying to patch an incorrect job. The pan should hold water if it was flooded, and that should have been done to pass the plumbing inspection. That is done prior to installing the final mud bed for several reasons, one being that they want to see if there are any depressions that might pool water, and that it can actually drain properly.

Now that you've cut the bottom off of the cbu panels, the bottom is not well anchored to the walls, as it will be at least a few inches up to where you can put any screws to comply with the whole idea of the pan is intact.

It's your house, you can do what you want. WHether or when you may experience problems is hard to predict, but the industry standards are written the way they are for a reason - they're known to work.