Prerequisites for installing a shower system?

[master_bather]

Hi, I'm trying to install a shower system with 3 body sprayers, a rainhead and a handheld. The connection sizes are all 1/2 in. We did a crude GPM test filling a 5 gal bucket from the hose and we got ~7.5 GPM. Our whole house is on 1/2 in copper -- reduced down from 3/4 straight off the meter.. (2 full baths in the house)

Should we run a 3/4 in line straight off the meter to the new bathroom and branch 1/2 in off from there for the rest of the house? Should I be actually verifying PSI instead of going off the fact that we are on city water and have great pressure to all existing fixtures? We are doing a full basement reno so have full access to plumbing.

I also didn't realize until finding this forum that total system output is limited to 2.5 gpm... could we even use this system in the US if the body jets are 1.5 gpm each, rainhead is 2.5, body sprayer is 2.0 and ideally we'd be using 2 at the same time?

Thanks to anyone who can enlighten us!

 

[Terry]

I normally run 1" from the meter for a two bath home.
3/4" to the water heater.
A bathroom with a tub would get 3/4" for the cold and 1/2" for the hot. That's for just one bathroom.
Is it code now for running multiple shower heads now? Not in most places. They do sell them though.

 

[Sponsor]

 

[master_bather]

Thank you, Terry! This is great info. I'm a little confused though - In the top table, is the Private Home column GPM ? and for the bottom table, is that the number of fixtures supported off of 80, 200, 300, etc. TOTAL feet of copper (as in all plumbing runs in the house add up to 200ft)?

 

[Terry]

Those charts are for the UPC code for fixture units. I don't know exactly what constitutes a fixture unit, but it is how they add them up.
When a tub is filling, it's 4.0 units, A shower head is 2.0 units. A washer is 4.0 units.
Its just their basic chart that has a plan for plumbing fixtures that use more or less water while being used. And we plumb to that to pass inspections.

 

[master_bather]

Those charts are for the UPC code for fixture units. I don't know exactly what constitutes a fixture unit, but it is how they add them up.
When a tub is filling, it's 4.0 units, A shower head is 2.0 units. A washer is 4.0 units.
Its just their basic chart that has a plan for plumbing fixtures that use more or less water while being used. And we plumb to that to pass inspections.

Thank you Terry, much appreciated!!