Supply Line Size for Rain Shower Head

Hello,

I have been posting some over at JohnBridge.com, but was recently directed here as most of my questions thus far involve plumbing and not yet tile.

That being said I am in the midst of my bathroom renovation and am presently running my copper supplies. So far I have everything run to the sink, toilet, and to the base of the shower rough valve. The shower is a standup shower with two shower heads and a diverter in the rough in, one regular shower head and one 8" rain. All of my supplies are 3/4" copper. My shower valve and shower heads are both 1/2" IPS.

My concern is regarding enough volume to feed the rain shower head

My question is....

Should I use a 3/4" to 1/2" IPS for connection to the shower valve and then continue 1/2" copper up to the shower head

-OR-

Should I just use 3/4" copper throught, always using 3/4" to 1/2" IPS all over

-OR-

Should I be using 1/2" IPS galvanized at all points beyond the valve?

Thanks for your time and help.

Alex

I was just researching the same thing... what size is the outlet for the shower head at the valve?

Never mind, I just saw that the valve and shower head are 1/2"... I would say you'll need to use 1/2" since going from 1/2">3/4" isn't going to do you any favors since the water acn only pass throught the valve via that 1/2" connection...

But that's just my guess.

Well, I just got off of the phone with the manufacturer and they confirmed what I had more or less planned.

Actually, I am going to be using 3/4" copper. The 3/4" copper is slight larger than the 1/2" IPS, but the 1/2" IPS is larger than the 1/2" copper. Due to this reason they have advised to use 3/4" copper as long as the supply coming into the shower valve is 3/4" copper. This will allow more water to flow to the shower head, and since no shower head sold is more than 2.5 GPM, and I have good water pressure from the city, the 3/4" copper will allow the shower head to completely fill up. I will notice more of a pressure drop if someone flushes the toilet or uses the sink, but I can live with that.

So I will be using all 3/4" copper and 1/2" IPS to 3/4" copper female connections.