Im installing a large new shower stall and i would like to install at least two nozzle heads across from each other. any ideas on a plan of piping layout and can i use 3/4 copper for more flow,I understand that i need a "closed loop" type piping.any advise or opinions are welcome-thanks

Use two shower valves. Increasing the size of the water piping will not let anymore water through the valve. I would strongly recomend using positemp valves to prevent scalding incase of pressure loss.

Mike

grohe makes a 3/4 valve check them out

Your water pressure may be horrible and no pipe size may be able to overcome it. It may be that you will need a booster pump to get the flow you are looking for. It wouldn't matter how many valves or pipe size increases you install. Luxury multiple shower head installations need lots of flow rate AND pressure availability to make folks happy. For your happiness, you'll likely need an experienced plumber to address this not just a guy who can install a shower valve or two.

President Johnson had his White House shower remodeled. The White House plumber said that the President wasn't satisfied until the multiple jets/heads had almost injurious force coming out of them. It took major plumbing work to achieve this.

you say to use 2valves i know but could you explain the piping layout. dont i have to tee both shower valves so the second valve isnt at the "end of the line".

I think I have good pressure coming from 3/4"pipes but how can i be sure what pressure.Ill gauge it ,whats the magic number 60-65 psig with no other fixtures used,then use certain faucets and check gauge for loss .Again what numbers am i looking for? THANKS

just did a 2 head system for someone. i used a grohe 3 way diverter. it is piped right at the outlet of the shower valve. turn the handle one way to get flow to head #1 another way to head#2 and another way to get flow to both. it was called a quattro diverter. #13932181

i would run 3/4 " tubing to a 3/4" shower valve. run it all the way from the basement and use "full bore" ball valves. configure your shower arrangement whichever way you decide is best.finish the job and try it out. if you aren't happy with the flow then install anything you want in the basement to give additional volume and pressure.

One more thing to think about...How are you going to supply this beast with hot water? If you have a standard 50 gallon electric water heater you are sunk! If it's gas you need to look at the gpm of all the stuff you are installing and planning to run at the same time and then look at the capacity in first hour rating on your heater.

If you have 2 shower heads at 2.5 gpm (flow restrictor in place) and 2 body jets at 2.5 gpm that's 10 gpm of flow! If you have a 50 gallon electric heater you will enjoy a very luxurious 4 - 5 minute shower. With gas conventional 50 gal. you might get 7-10. Some units have jaccuzzi style recirc pumps that help eliminate this issue but cost a bit more money going in.

Just do a bit more math to figure on your whole project and what the changes will cause before you get a big (cold) surprise.

You may have already thought all this through, but I though I would bring it up.

This is just in the planning stage of course but anyway what if i pipe 3/4"to the main valve/diverter and1/2to the 2nd nozzle?

This sounds like what Im looking for,does it work like its supposed to?how's the user like the setup.Also does this require more extensive piping I would think you would need to.

Sorry Packy I didnt read your next reply before I engaged my fingers.So what I think you're saying is to run separate 3/4" lines from W/H dedicated to shower?

here's the info on the installation i just did. hans grohe ecostat mixer 15374184 (3/4"13.2 gpm @44psi...hans grohe volume control h13975181 and Quattro diverter 13932181...yes, run 3/4" dedicated lines from basement to shower valve with "full bore" ball valves. from the diverter run 1/2" to each shower head. i hope these numbers are correct. they are for rough fittings only. the trim for them has to be chosen by you. chrome plated,rough brass,or whatever.i don't understand how it works but the quattro diverter has 3 positions. one for head #1, another for head #2 and somewhere in the middle for both heads. you don't put it all the way to the 3rd position. i was sceptical but it does work well. as i said earlier, do all this and try it out. if you don't have enough flow, at least the two 3/4" lines are run from the basement and if you want you can bring in a 6" main from the street and you'll have so much water you'll have to strap yourself into the shower or you'll be blown out the door... :>

Dear Packy, do you have a diagram for your ultimate arrangement? Or do you know where i might find one? Thanks Nad

dear Mike, do you have a diagram or do you know where i might get a detailed installation schematic from? thanks nad

Your message refers to a Hansgrohe model number, not a Grohe model number.

Do any of you know if the Grohe 3 port diverter/transfer valve (29712) allows both shower and handheld to operate at the same time? One of my suppliers says yes, the other say you can only operate one at a time.