2 heads, very different gpm

I need to install a rain shower head (8" diameter) as well as a handheld shower off the one valve and I want to avoid this setup being uneven in its distribution of the water (which I've seen more often than not with multi heads). I'm worried about this issue with the drastic difference in head style, and am not sure about my plan of action for it. Could you give me any suggestions or recommendations that you've learned from doing this? hj, I'm sure you'll have plenty for me

Both heads will be rated at about 2.5 GPM because that's the law! But you will have balance issues if the piping system is not designed with loops for multi heads. Also, do you know if the supply to this shower valve is capable of delivering enough water for 2 heads?

I have to check the specifics of it all when I see it again tomorrow, but it's all imported european stuff; valve and heads. The building is a condo in a commercial zone which should have lots of pressure available, and the supply pipe to the existing shower is 1/2" copper so that's what I have to work with. Client has purchased everything and just needs it installed, but I want to avoid installing it and then having a shocked "but why isn't it working?!?" coming down on my shoulders...

heads

You are going to have a pressure differential regardless of how you pipe it because the hand held is going to be lower than the rainfall one. And since the valve's output will be a finite amount, if the handheld is on at the same time as the rainfall, it will take its design volume of water and the rainfall will get whatever is left, and putting a loop will not change that.

why not a diverter past the valve? use either the head or handheld. not both at the same time.

That is my concern, that this rainshower head is going to dribble away and be useless... sounds like one at a time is the best option. Thanks for the input guys, I really appreciate it...