[jedapo]

I am replacing my old shower that had one head with a new luxury shower from Kohler that will have three body washes(24 holes each), a hand held, and a regular shower head. I have 1/2 inch copper coming into the shower from the slab. Seeing that I have 1/2 ", should I buy a 3/4" or 1/2" master valve. If I buy the 3/4", would I then then run 3/4" to each head or go back to 1/2"? I have been looking at some new houses going up and they have 1/2" from the slab to 3/4" valve and then back to 1/2" to each head. I hope this makes sense. Thanks in advance.

[massplumber2008]

Hi Jedapo...

For everything you just mentioned I think you really need to supply the shower valve with 3/4" tubing and use a 3/4" mixing valve.

Feeding 1/2" into a 3/4" mixing valve is a waste of money... ok? Feeding 1/2" into a 1/2" valve and then braching off to all 3 body washers and shower head will definitely leave you dissapointed when you turn shower on for the first time!

Kohler has a MINIMUM volume of water or pipe size required for your system. When you pick out the correct mixing valve it will tell you all requirements for multi. Head system.

Let me know if need more on this...

MARK

[jedapo]

Thank you for your advice. I thought the same. I guess my question now would be that if I have 1/2 copper coming out of the slab, do I just attacth 3/4 to it (which I know I can do) and then continue onto everything with 3/4? I can't change the 1/2 in that comes out of the slab.

[speedball1]

I guess my question now would be that if I have 1/2 copper coming out of the slab, do I just attacth 3/4 to it (which I know I can do) and then continue onto everything with 3/4?

Save your time! It wouldn't change the volume a bit. You would still be choked down to 1/2"
In that case if I wanted to maintain the volume needed I would cap off the 1/2" supplies and tee off the hot and cold 3/4" mains, run them overhead in the attic and drop down to pick up your 3/4" mixing valve. Good luck, Tom

[jedapo]

Save your time! It wouldn't change the volume a bit. you would still be choked down to 1/2"
In that case if I wanted to maintain the volume needed I would cap off the 1/2" supplies and tee off the hot and cold 3/4" mains, run them overhead in the attic and drop down to pick up your 3/4" mixing valve. Good luck, Tom

Thanks Tom. We both know that's not going to happenl.. too mcuch work. I guess I'll just go with the 1/2" and hope for the best. I assume I won't even be able to use both the body wash system and the shower head at the same time (guess I'll just have my wife hold a separate hose over my head:)). It just seems weird that all the houses I see that are roughed in mostly have 1/2" coming out of the slab and then go to 3/4". The Kohler valve spec just says I need 15psi....I have 40psi at the outside faucets but not sure out of the 1/2" at the shower.

[massplumber2008]

Hi Jedapo:

15 PSI and 3/4" tubing for VOLUME needed for multi.shower system...;)

1/2" will work, too... just won't have the volume to knock you over is all! The idea of enlisting wife's help is always a good idea!

Choose the mixing valve you want and then read up on the instructions... should give you a pressure/volume curve to determine your requirements!

Good luck!

MARK

[jedapo]

Thanks a million guys... I will check with Kohler tomorrow to see what they say. I do want it to knock me over when I take a shower if I want to but I would hate to put 3/4 all over the place and have the water just dribble out. The water/volume equation is way over my head.

[massplumber2008]

Let us know if you want to discuss more once you get the details!

Thanks you..

MARK