View Full Version : Sealing tub spout against tub surround?

01-23-2009, 08:43 PM
I have a Moen tub and shower faucet in a new basement bathroom I just finished and the last detail I am concered with is the seal where the tub spout meets the tile surround.

I was surprised to find the tub spout screwed onto the nipple and the length of the nipple determines the standoff of the spout from the surround - I needed an odd size nipple that I had to order from Mcmaster Carr, but I finally got the spout to seal the NPT threads before it hit the surround. Now I don't know what to do where the spout meets the surround. Any advice? Plumbers putty in the opening between the tile and the nipple maybe? Surely caulk is not the pro solution here.

01-24-2009, 05:49 AM
Why not caulk? Plumber's putty will harden and discolor, and possibly stain the surround.

01-24-2009, 08:04 AM
That gap is too big to caulk attractively. Get a matching BN tub spout "spacer" . Most hardware or plumbing stores will have something like that.

01-24-2009, 03:05 PM
That is supposed to sit flush against the wall. It's not supposed to stick out like that.

Your nipple is too big. Remove it and install a shorter nipple. I believe they come in half inch increments.

Any thing you use too fill that gap will be ugly.

Are you sure you tightened it all the way?

01-24-2009, 04:40 PM

You are correct, nipples come in 1/2" increments and if I use a 1/2" shorter one, the tub spout will bottom out on the surround wall before the NPT fitting is tight. The one in the pic is nice and tight - too tight to get another whole turn. I don't believe a well engineered system would expect the installer to achieve a seal with the NPT threads while simultaneously seating against the tub surround. The spouts I've used previously have used an O-ring that slides along the OD of the nipple and a setscrew. This allows one to achieve a watertight seal while enabling proper positioning of the spout relative to the surround. I can get the shop at work to make a 1/4" shorter nipple, but I'm disappointed that one would have to go to such lengths. If this spacing was so critical I would have expected Moen to call out a setback for the rough-in elbow that receives the tub spout nipple or something. I guess I'll get the shop to thread me a 1/4" shorter version and see how close I can get it. I remain disappointed in this brand.

01-24-2009, 07:16 PM
The O-ring is great. That was kohler right?

Quick question, when you look inside your spout is there just female threads stationed at the very end?, or is there white plastic with female threads inside, but also threads on the white plastic as well that allow you to move the female threads up and down? This design allow for plenty of play.

If the former, try and tightening the nipple first against the drop ear elbow as much as you can, and then tighten the spout as much as can till it hits the wall, if it doesn't tighten all the way(with all your might) ,but it's snug, I think you will still might be good. Check for leaks and use teflon tape.

It shouldn't be that much hassle to get the length you need. Plumbing supply stores will thread the pipe for you.

By the way, can you post a pic of the entire shower body, I want to see how far the handle sticks out. It was in another thread. I keep hearing complaints about Moen. I won't ever touch them again.

02-23-2009, 03:38 PM
I'll mess around with the idea of getting the nipple the correct length but it seems poorly engineered.

In the meantime, even if I get the spout to seal and simultaneously touch the surround wall, is the metal tub spout sitting against the surround wall considered acceptable as this would obviously not be a watertight seal. My concern with this entire installation is that I don't want water to get behind the spout when someone is showering and find its way into the wall cavity. I have plumbers putty around the nipple where it exits the tile - is this considered sufficient or should I opt for silicone or something there?

02-23-2009, 04:59 PM
I sealed the pipe that comes out for the spout 1st
Then put the spout on

Gary Swart
02-23-2009, 05:26 PM
I used a copper male adapter into the spout then measured the space I needed to the elbow on the pipe leading from the valve and cut a piece of copper pipe that with another male adapter made the space small enough that the threads on the spout easily brought the spout tight against the surround. I didn't even need to caulk it.

02-24-2009, 08:04 AM
Some spouts and other shower components are VERY critical about the proper length. Try installing some Kohler stuff...1/16" accuracy is required if you want things to fit nicely I've been told.

I read about one screw on spout that had a two step adjustment...the threaded portion had a little movement on it so you could compensate for variations like you are seeing. Is there any part internally to that spout that looks like it could be adjusted? If not, then a custom nipple, or a piece of copper (or brass) pipe with soldered on male adapters may be the only answer.

Gary Swart
02-24-2009, 02:05 PM
I used Delta components. The threads on the male adapter that screw into the spout give a reasonable amount of adjustment so measurement does not have to be the the Nth degree. I can speak for other brands.