double-shower install -- rip out and do over???

[John]

I had a contractor build me a shower with two sprays -- one on the front wall, the standard location where the shower typically is. The other is overhead, so we could have the total-immersion, perfect-storm effect. The problem is, he didn't understand that we wanted both showerheads to work simultaneously. He installed a diverter -- switch it one way, the water comes out the overhead spray, switch it the other way, the wall spray. Everything is finished and tiled, and I'm very unhappy.

So my question is, how to fix. Even though the diverter is graduated (meaning that if set at the halfway point, water comes out of both sprays at once), this is NOT a solution; you only get 50% pressure out of each spray when you do this. Not good. I would like as close to the max 2.5 g/psi coming out of both simultaneously. Assuming we're going to have to rip out some tile/backerboard, what's the best way to get to simultaneous strong flow in each showerhead? Do I need some other kind of fixture? The fixture installed is a Delta Monitor, 1700 series. Thanks for your thoughts.

[Speedy Jim]

Hmmmmmmmmmmmm. Considering the cost of ripping out just one tile, let alone a bunch of 'em, I think I'd try some experimenting. Remove the diverter control and drill/file/grind whatever so that both ports are open all the time. Go to Delta's site and download the file on the Monitor to see what it's made like. (I'm not familiar enough with that series.)

Jim

[Art Todesco]

[m Ransley]

It actualy does come out of both heads then its just you dont like the low pressure. Wouldnt 2 separate valves be the same. I think , im not sure here,, you really need to double the water piping supply, or volume delivered

[PJx]

Are you sure your plumbing will support two shower nozzles at once? My hot water run is 40 feet of 20 year old copper and I'm not sure I could run two nozzles at once.

Can you replumb while you are at it?

PJ

[Al]

The plumber may have had to do what he did because of plumbing codes. My code says 2.5 GPM max for a shower. The local building inspector may have interpreted that to mean all shower heads and not just one.

If your diverter is installed in the wall then you are looking at trouble. You could take the diverter face plate off and see what kind of piping was used (ie Pex, copper, CPVC, or other) and see if it can be routed around the diverter with a slight modification. I would leave that to a pro since it is almost impossible to do. It may involve popping off several tiles so the plumber can get his torch in (not the case with plastic pipes). Pay the money and call the plumber that installed it.

Your other option is exactly what Speed Jim said and that is to modify the valve. Most diverters use a gate valve style arrangement. Depending on the piping size you should be able to run two 2.5GPM showers without a significant pressure drop unless you have 1/2 piping and your shower is located several stories off the ground. I dont think that is your case.

I hope this helps, Al

[Halvey]

[Jeff Cochran]

You'll likely need an upsize in supply piping to achieve this, and it may not be allowed in your building jurisdiction. Sit with your plumber and discuss options.

Jeff

[John]

I understand that two 1/2" branches off the 1/2" supply will reduce the pressure, but certainly not by the 50% reduction I get through each sprayhead when the diverter is set at halfway. I should be able to test this by turning on this shower -- the master bath -- and then going out in the hallway bath and turning on that shower. I don't think I'll see 50% reduction back in the master bath, and it's the same thing, right? two open faucets, each branching off the main supply?

The contracter, however, tells me that what I want isn't possible with

1/2 supply.

[Speedy Jim]

More than likely, he's blowing you off cuz fixing it will be a headache.

1/2" supply should be _more_ than adequate, especially with low-flow heads.

Quick experiment: Remove wall shower head. Screw on a 1/2" TEE. Couple of EL's and some nipples and put 2 heads on the TEE. Set diverter to supply just the wall outlet.

Now, if there is inadequate flow from the 2 heads in this experiment, the Delta control may be too restrictive.

But if it *does* work satisfactorily, look at modifying the diverter or, maybe, reworking some piping via the adjoining room (cut hole in drywall). Jim

[m Ransley]

1/2 inch -2 heads- it depends on house pressure. Probably 3/4 is needed for your situation

[Yasashii Arbaito]

As you have no doubt guessed, diverters are not really designed for this kind of mixed output. I just looked at a Delta diverter, and the total open output area at the 50/50 position looks substantially less than at either 100% position.

I'm assuming you have a Delta pressure-balance valve (e.g., 1725) and a separate diverter. The specs on the Delta are not as good as some other makes. It looks like you need 60psi in order to get a 5gpm flow rate. By contrast, the Grohsafe 35 253 achieves this at 30psi. But, 60psi is hardly unusual, so there's a good chance your valve could deliver enough water with the right setup.

The real "right setup" would be to have a pressure-balanced or thermostatic mixing valve with no volume control, replace the diverter with a simple tee, and then have separate volume controls for the two shower heads. This would give you complete control and maximum flow to both heads.

Failing that, you could try gutting the diverter - not sure how yours is, but mine (for a Roman tub filler, however) has a separate "diverter assembly" which it looks like you could remove to convert the thing to a plain tee. If you go this route, you might also try removing the flow restrictor on the overhead shower only - since it's higher up, it will have less pressure than the side one, so this might partially compensate.

If that doesn't work, you'll have to make more thorough-going plumbing changes. Do this from the other side of the shower wall, assuming it's just plain drywall or the like.