Copper vs Pex

[knichel]

I am renovating bathrooms in my house and wish to use PEX (expanding kind). I have the materials already.

My question is this... There seems to be differing opinions on running PEX from the shower valve to the shower head and tub spout. Some say why not go with PEX and others say ALWAYS use copper here, PEX is OK to supply the valve.

What is the consensus on this and what is the rationale?

 

[Matt30]

Feed 3/4" as close as you can to the shower control, reduce to 1/2". Pex is fine for your standard shower (no body sprays or wands).

 

[phishfood]

Most valve manufacturers specify to NOT use PEX to the tubspout.

 

[frodo]

i would take it a step further. no pex on the shower riser either.

why??????
down the road, when mr homeowner wants to change out the spout or shower head.

try's to remove the old. and does nothing but twist off the plastic tubing.


also. the pex is a smaller id of pipe than copper on a spout or head you want volume

of water
pex
http://screencast.com/t/NVUpUnSrdPzZ

copper
http://screencast.com/t/6bT6cal3B4

 

[knichel]

Thanks for the replies. The tub and shower head will be connected to drop ear el's screwed to 2x6 blocking so they will not have any issues with spinning off the plastic.

So WHY do they suggest not using PEX? With pex being so popular and easy, why aren't they re engineering their products with pex in mind...

 

[Matt30]

Definately no pex on the tub spout, I kind of assumed that was a given.

 

[frodo]

i take it you did not understand my previous post.

it is a volume issue. when you take a shower do you want full stream of water or do you want a stream like a 70 year old man taking a leak ?

the bigger the pipe the more volume of water, the smaller the pipe the less volume


pex ID on 1/2 pipe is .485

copper ID on 1/2'' pipe is .666

the manufacture warns, do not use pex

 

[frodo]

use a brass nipple/ a brass 90 NOT STEEL OR GALVINISED

 

[knichel]

Thank you frodo. I purchased a brass 90 with the tabs for screws. Im going to use copper for tub and shower and keep pex to supply valve.

 

[Ewhitaker0020]

i take it you did not understand my previous post.

pex ID on 1/2 pipe is .485

copper ID on 1/2'' pipe is .666

the manufacture warns, do not use pex

Isn't the ID on 1/2" copper smaller than .666?

 

[frodo]

.http://screencast.com/t/6bT6cal3B4

seems you are correct. it appears I erroneously sited the ID for 5/8 tubing

to this i apologise to the 1/2'' pipe God, hopefully he will not be offended

it is '.569 for type L copper [type L is allowed under the slab in residential, type M is not}

I am most humbled and thank you for your correction

 

[Ewhitaker0020]

Sorry I didn't mean to make you mad. I was just asking because I was confused.

 

[frodo]

Sorry I didn't mean to make you mad. I was just asking because I was confused.

i am not mad,,sometimes my humor ''reads' like sarcasm

i was joking, not whining....

 

[Ewhitaker0020]

One thing I am confused about is how can 1/2" copper be thicker than 1/2" on the ID? Isn't the OD supposed to be 1/2"? I'm new to plumbing in case you can't tell.

 

[frodo]

copper tubing is a nominal measurement