Shower system help

Discussion in 'Shower & Bathtub Forum & Blog' started by chuc, Sep 30, 2020.

  1. chuc

    chuc New Member

    Sep 30, 2020
    Hi all,

    Thanks in advance for any help here. We are doing a bathroom remodel and I feel like everyone I talk to gives me a different answer--even employees at the same plumbing supply store. I'm hoping to arrive at some sort of consensus.

    Our bathroom is completely torn apart, but here is a rending of the remodel we are doing:


    Obviously the valves are missing here, and that's what I'm trying to figure out. I really wanted to put the shower heads on their temperature and each group (of three) body sprayers could be on their own temperature and volume. The salesman we worked with at the plumbing store suggested we go with Moen and use five 1/2" Moentrol valves for everything. So, we'd end up with 5 Moentrol valves and handles looking like this:


    Conceptually, I really like this idea, but I was worried about water pressure in this scenario. The Moen body sprayers were 2.0gpm each, but we also looked at ones that were 2.5gpm each. We had talked to another salesperson at the same store that insisted that 3/4" supplies should be run if we're using body sprayers. The salesman suggesting the 5 Moentrol valves (push/pull for volume, turn knob for temperature), however, insisted we'd have plenty of pressure and that the heads only connect to 1/2" supply lines anyway, so there was no sense in using 3/4" supply lines. I do have access to the 3/4" lines coming off the main, FYI.

    Confused, I called Moen today, but since I'm not a contractor, they wouldn't let me talk to their "pros," so I had to try to relay all of this information over the phone to a lady that would put me on hold and talk to the pros and then relay their response back to me. They suggested using two 3/4" thermostatic valves for each side, with separate volume controlling diverters for the different heads. It seems like this is what most people were suggesting when we went out shopping, but it doesn't solve my desire to be able to control temperatures separately (the reason I want this, JFYI, is because the rainfall shower head, hand shower, and body sprayers will all be different distances away, and it seems like it would be really nice to tweak the temperatures separately just how you want them).

    On top of all this, the people doing my remodel have just said that if the pressure isn't where I want it when they are done, they can "add a chamber of air to the water lines of the house."

    I'd really appreciate any advice on how to handle this situation.


    EDIT: If anyone is in the SLC and knows what they are doing, I'd be happy to pay to have this done properly. It's so hard to find plumbers right now.
  2. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Sep 2, 2004
    Retired Systems engineer for defense industry.
    New England
    FWIW, the copper institute highly suggests you don't try to move water through the pipes with hot at greater than 5fps. With a 3/4" supply line, that's 8gpm. So, add up the outputs of what you think you'll want on at the same time, and then, even 3/4" lines may not be enough. I haven't got a clue what the guy meant by adding an air chamber...I can't see that doing anything for your pressure, but I'm not sure what he meant!

    You'll be mixing some cold into your line, but probably the highest capacity 3/4" valve you can find is around 15gpm, and most 1/2" valves pretty much top out at 6 gpm or so.

    On a tank, you can usually get around 75-80% of the capacity before you notice the outlet cooling off. If you choose a thermostatically controlled valve, it can self-adjust the hot/cold mix to try to retain your set temperature, but it can't make hot water! A typical thermostatically controlled valve tends to be able to flow a bit more volume than a single handle one, too. You're going to need a really big water heater, and if you think about going tankless, probably more than one to get the volume you are expecting and the temperature rise. That may mean upsizing your gas line from the street and a bigger meter, too. SLC probably has hard water, so tankless maintenance would be a pain, less, if you have a water softener dialed in properly.

    Rain shower heads are pretty poor if you're trying to rinse shampoo out of your hair, and maybe worse for conditioner.

    For the shower construction and tiling, check out There are numerous ways to build a successful shower, but they are need to know what you're doing. One study I read a long time ago said that 75-80% of tiled showers were not built to industry standards, and that can lead to an expensive mistake! It's not rocket science, but it is exacting...miss one step, and things can fail. Looking good is one thing, but it's what's underneath that keeps your house and performance up. The tile is the aesthetic, not the structural component of building a shower. You need both to be done right.
  3. Sponsor

    Sponsor Paid Advertisement

Similar Threads: Shower system
Forum Title Date
Shower & Bathtub Forum & Blog Signature Hardware shower system Jan 8, 2020
Shower & Bathtub Forum & Blog Converting 1 shower head system to a shower head +++ Jan 2, 2020
Shower & Bathtub Forum & Blog Selecting a shower system manufacturer May 7, 2019
Shower & Bathtub Forum & Blog Shower Rise With newly installed PEX addition to copper system Jan 24, 2019
Shower & Bathtub Forum & Blog Delta shower system not diverting to handheld May 17, 2017

Share This Page