Installing Shower Valve

jelly · 07-03-2011, 10:06 AM

I am getting ready to put a new 60" tub where an old 59" cast iron tub used to be. I need to move the supply lines and am having a hard time reading the manual that came with the valve.

Do I have to install the tub before mounting the valve? The first diagram below shows the dimensions based on the tub already being installed. It would be much easier to install the valve if the tub wasn't already in place.

The second diagram is confusing to me. In 2A and 2B the valve is centered in the stud but in diagram 2C the valve is flush with the stud face. How do I know which letter to follow? (A,B or C) There are no instructions in this manual other than pictures.

Cheers.

**oh'mike** · 07-03-2011, 10:36 AM

B--is typical for a Moen mixer with tile---a 2x4 block to the back of the opening places the front of the valve properly for 1/2 inch Durrock and tile.

check this for your self by holding the valve ,with the black plastic tile ring , into the pocket and checking the face of the tile ring to the face of the tile--(usually 3/4" --thicker tile might bring that out to 1")

You can install before tub goes in.--Mike---

jelly · 07-03-2011, 01:02 PM

Does the 1/4" in [2B] represent the recessed distanced from the stud face?

**oh'mike** · 07-03-2011, 01:09 PM

I can't make out the drawing,Sorry.----All I know from having installed dozens of these moens is that a 2x4 block against the back of the studs puts the mixer right for tile.

Check it out--mount the plastic tile guard and measure it. If it's right you're good to start.

the face of that guard should end up about 3/4" out from the face of the studs (1/2" rock + 1/4" or so for tile)

jelly · 07-03-2011, 01:45 PM

Thanks. Here is the complete manual:
http://www.build.com/mediabase/speci...en_82910is.pdf

If you are suggesting the 5" black plastic guard should stick out 3/4", I should follow "C" and not "B" correct?

Alan · 07-03-2011, 02:09 PM

Quote:

Originally Posted by oh'mike

I can't make out the drawing,Sorry.----All I know from having installed dozens of these moens is that a 2x4 block against the back of the studs puts the mixer right for tile.

Check it out--mount the plastic tile guard and measure it. If it's right you're good to start.

the face of that guard should end up about 3/4" out from the face of the studs (1/2" rock + 1/4" or so for tile)

Not down talking you, but it always depends on who does the tile.

We have guys here where we figure 1-1/4" for the front face of the plaster guard. One time we did that, and it was still 1" too deep in the wall.

We asked what happened, and the tile guy says "The room was out of square so we had to float the entire wall.

W - T - F ?

Check with your tile guy for wall thickness, and if you're the tile guy, it should be no prob.

As you can see by all of those diagrams the front face of the plaster guard is within 1/4" of behind the finished surface.

**oh'mike** · 07-03-2011, 02:13 PM

[quote=Alan;679084], but it always depends on who does the tile.

That's exactly why I told him to get the valve and ring and see how far out it needs to be to clear the rock and tile.

jelly · 07-03-2011, 02:30 PM

I will be doing the tiling.

Thanks for confirming that I need to follow "B" Sorry for all the questions but this is the first time I am attempting to do this.

Just to confirm, I am going to position the face of the 4.5" plastic guard (part E) so that it sits 1/4" behind the finished tile and the cement board will butt up against the 4.5" plastic guard?

Much appreciated...

Alan · 07-04-2011, 11:58 AM

Quote:

Originally Posted by jelly

I will be doing the tiling.

Thanks for confirming that I need to follow "B" Sorry for all the questions but this is the first time I am attempting to do this.

Just to confirm, I am going to position the face of the 4.5" plastic guard (part E) so that it sits 1/4" behind the finished tile and the cement board will butt up against the 4.5" plastic guard?

Much appreciated...

Yes, backerboard and tile up to the edge of the plaster guard. That will ensure that your cover plate will hide the hole behind.

jelly · 07-04-2011, 12:09 PM

Quote:

Originally Posted by Alan

Yes, backerboard and tile up to the edge of the plaster guard. That will ensure that your cover plate will hide the hole behind.

Thanks Alan. I need to follow the "B" portion of the instructions but the diagram [3B] shows the guard hidden behind the backerboard while in [3C] the guard comes through the backerboard so I can tile up to it per your instructions.

The MOEN instructions are horrible.

**oh'mike** · 07-04-2011, 12:36 PM

Real men don't read instructions!

Alan has it right---the face of the plaster ring should end up approximately flush to the tile surface--

Moen is fairly forgiving---and an extension shaft set is available if you set it way to deep---don't ask how I know that or why I know that the set cost $35--last month.

---Mike---

**oh'mike** · 07-04-2011, 12:41 PM

Use 'eared flanges' for the shower and tub spout---screw solidly to blocking.

Insert temporary capped stubs to the flanges so you can test your work under pressure.

Always use dope and tape (yes,both) when installing the shower head arm---that is a very common cause of a leak in a shower installation.

jelly · 07-04-2011, 02:13 PM

Thanks for the tips Mike.

So this is how it should look after I hang my backerboard?

**oh'mike** · 07-04-2011, 04:07 PM

That looks about right---I could tell you exactly if you had a piece of tile against the wall---

guyinsb · 10-17-2012, 01:43 PM

The plaster guard does indeed serve a use. There is a gasket on the back of the circular chrome trim which needs to butt up against something firm
to create a good seal. Without the firm fit, the gasket will sort of work, but at some point in the future (22 years for one of my Moen valves),
the gasket comes loose from the trim, and water leaks behind the valve (down to the ceiling in the room below, in my case!).

I jerry-rigged a plaster guard substitute out of a circular piece of stiff plastic; am installing this afternoon.