Good Evening, much lurking, first posting. Plumbing shower to be tiled over kerdi. Just where do you locate the drop ell relative to the backer board ? I mean should it protrude into the backer board, where you could caulk it right to said board. Or should you leave it deep in the 2x4 wall, say plumb with the shower valve and let the nipple reach out. This is for a shower head, handheld shower and a couple a body spritzers. Oh yea, and is 1.28 gals. from the Guinevere really gunna take it all to the septic tank ? Thank you in advance.
Last edited by Terry; 06-02-2010 at 02:17 PM.
Last edited by Doherty Plumbing; 12-03-2009 at 07:05 PM.
I am using Moen fixtures (handheld, rainhead, and body sprays) in my shower build. The handheld has a fitting (a drop-ell in brushed nickel in my case) that attaches the shower head hose to the wall. This fitting threads onto a pipe nipple pipe nipple that needs to be recessed below the tile surface by 1/4 to 3/8 inch (there is no escutchon plate). The body sprays requires that the pipe nipple extend past the tiles surface by 1/2 to 5/8 inch (then an escutchon plate covers the opening). The rain head threads into the (female thread) drop-ell which is below or even with the tile surface (then escutchon plate covers the opening). So, I'm saying it depends on the fixtures you buy how far back in the wall the drop-ell gets mounted.
I would use 100% silicon sealer around the hole then put escutchon plate on.
You install the shower/tub valve according to its requirements, then go to the shower and down to the spout's, (if you have one) drop ear elbows and fasten them where ever they happen to come out. The only way you would normally be able to adjust it in or out is if you used flexible PEX tubing, and you probably do not want to do that, unless it is a shower only installation.
There is NO standard; it depends entirely on the brand and model you choose to install. Some require VERY precise positioning, some are very loose. The only safe thing is to mock it up. Some give a min/max, but people often don't like it at the extremes. Only you can tell, unless they give you NO tolerance, then you better be exact.
As to sealing things around the penetrations, this isn't normally all that big a deal unless it is a steam shower. The combination of the eschution and its built-in seals is normally plenty to prevent water from getting inside the walls, especially high up there when the shower head is not pointing at it.
Schluter does make gaskets if you really want to use them, or suggests KerdiFix (a urethane adhesive) to seal and adhere to the Kerdi membrane.
Important note - I'm not a pro
Retired Defense Industry Engineer
I'm dry fitting all the pieces before I install my shower. I'm finding that if I go straight up from the shower valve and attach a drop ear elbow, the threads will be about 2 1/2 inches inside the wall from the surface of the tile. Is this normal? It seems really far back.
It is fine, the arm is at least 4" long, and more likely about 6".