Shower remodel to tile, position for face of valve rough in

[Jetada]

Hi guys. I have a potential problem. Well I don't know if its a problem. I need to know if I need to address this before I install the tile.

I replaced the old bathtub and stripped the sheetrock from all the walls. Due to the studs not being plumb and difficulty installing the new tub, I had to shim out the wall where the valve is by 1/4 inch. On top of that I installed hardibacker to prepare for installing wall tiles in the shower. The previous shower walls had sheetrock and then a thin plastic shower wall liner.

I waterproofed the seams with fiberglass tape and waterproofing compound. I installed new sheetrock, finished the seams, applied texture and painted. Now I am ready to install tile.

However, I picked up the tub trim kit and wanted to make sure it would work. The face of the valve assembly only protrudes about 1/4" from the face of the hardibacker board. With a piece of tile behind the trim, the center of the valve assembly no longer pokes through the trim piece.
See picture.

Also keep in mind there will also be 1/8" think layer of mortar. So the front of the valve will be closer to 1/4" behind the plane where the trim piece is.

Is this a problem? Will it cause water to leak behind? Will I be able to attach the handle?

Do I really have to cut the hardibacker and move the valve assembly? Are there any adapters that will make this work?

I would greatly appreciate any advice. Thank you.

 

[Terry]

Moen makes a 1" handle extension for that. 10399

 

[Sponsor]

 

[Cacher_Chick]

You also need to apply waterproofing to the backer board before you tile. Neither tile or backerboard is impervious.

 

[Jadnashua]

CBU above the tub or shower pan doesn't need to be waterproof (it doesn't hurt and can help), but you do need at least a vapor barrier behind it if you are not going to use a topical waterproofing. While cbu is not waterproof, it is not damaged if it gets wet. Now, to keep condensation or other sources of water from damaging things behind, if you don't do a topical waterproofing, you need at least a vapor barrier (typically plastic film or roofing felt) behind it to prevent any moisture from damaging things behind it that shouldn't see moisture. FWIW, neither tile nor grout are waterproof, they are the decorative, wear layer.