Selecting Pex Line Size? - Plumbing - DIY Home Improvement | DIYChatroom
Advertisement


Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Plumbing

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread
Display Modes
Old 09-19-2015, 11:08 AM   #1
Member
 
Join Date: Jul 2012
Location: Massachusetts
Posts: 389
Rewards Points: 290
Default

Selecting Pex Line size?


I'm finishing up my man-cave, complete with a bathroom and wet bar. My house is primarily Copper pipe throughout, but for ease and cost reasons, I'm likely going with PEX to plumb the fixtures.

My problem is this: I don't know what size Pex to use (I know the inside diameter of Pex is less than that of copper)!

Coming off of the meter, the main water line is 1" copper. My bathroom is about 20' away from the line where I'd tee into.

My real problem is in the bathroom, I'll also be installing a urinal with a 3/4" flushometer.

Knowing this: Should I Tee off the main water line, then run 1" Pex all the way to the bathroom, and then Tee off again for the bar sink/dishwasher, bathroom sink, toilet and then reduce down to 3/4" for the urinal?

Or should I be okay Teeing off of the copper main, and running 3/4 PEX and Teeing off of that for the other fixtures?

Thanks for any help!
gizzygone is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 09-19-2015, 04:53 PM   #2
Plumber
 
TheEplumber's Avatar
 
Join Date: Jul 2010
Location: North Idaho
Posts: 11,384
Rewards Points: 170
Default


Run 1" to the bathroom. Also put an water hammer arrestor at the urinal
__________________
When posting in forums, letting us know your location will help others give better feedback/advice/solutions to your questions
TheEplumber is online now   Reply With Quote
Sponsored Links
Advertisement
 
Old 09-19-2015, 05:31 PM   #3
A "Handy Husband"
 
rjniles's Avatar
 
Join Date: Feb 2007
Location: South Carolina Low Country
Posts: 11,078
Rewards Points: 796
Default


I would run 1" for the cold. Hot depends on what fixtures you will have.
__________________
My electrical answers are based on 2017 NEC, you may have local amendments.

Location: Coastal South Carolina
rjniles is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 09-21-2015, 07:24 PM   #4
Master General ReEngineer
 
Bondo's Avatar
 
Join Date: Dec 2007
Location: Greenfield Maine
Posts: 9,462
Rewards Points: 1,034
Default


Ayuh,... Agreed,... 1 inch to the urinal, the biggest water user, then else where,...

probably 1/2" will easily feed the other uses,....

"T" off the 1" goin' by it, if necessary,....
Bondo is offline   Reply With Quote
Old 09-21-2015, 07:32 PM   #5
Member
 
Join Date: Jul 2012
Location: Massachusetts
Posts: 389
Rewards Points: 290
Default


So bring a 1" main all the way to the urinal, before reducing to a 3/4" copper line to the flushometer?

Are we saying I shouldn't be putting a T on the 1", and that I should be using a separate 1/2" pex to the toilet and two sinks for the cold?



I thought the standard for sinks were 3/8" lines?
gizzygone is offline   Reply With Quote
Old 09-21-2015, 08:00 PM   #6
Plumber
 
TheEplumber's Avatar
 
Join Date: Jul 2010
Location: North Idaho
Posts: 11,384
Rewards Points: 170
Default


1" to the urinal. Reduce to 3/4" to supply one of the 3 remaining fixtures. Then 1/2" to the last 2 fixtures.
Also include a water hammer arrestor for the quick closing urinal flush valve.

Sinks and toilets are 3/8" but that is only the exposed supply lines. Inside the wall is typically done with 1/2"
__________________
When posting in forums, letting us know your location will help others give better feedback/advice/solutions to your questions
TheEplumber is online now   Reply With Quote
Old 09-21-2015, 08:54 PM   #7
Member
 
Join Date: Jul 2012
Location: Massachusetts
Posts: 389
Rewards Points: 290
Default


Sounds good. 1" all the way to the urinal before I "t" off.

Is there any reason to put a manifold in? Or is a couple of T's okay?


If I decided to go with copper instead of PEX, could I tee off before the urinal?
gizzygone is offline   Reply With Quote
Old 09-21-2015, 09:29 PM   #8
Plumber
 
TheEplumber's Avatar
 
Join Date: Jul 2010
Location: North Idaho
Posts: 11,384
Rewards Points: 170
Default


Quote:
Originally Posted by gizzygone View Post
Sounds good. 1" all the way to the urinal before I "t" off.

Is there any reason to put a manifold in? Or is a couple of T's okay?


If I decided to go with copper instead of PEX, could I tee off before the urinal?
No need for a manifold.

Yes, you can tee off before the urinal, but the pipe size continuing to the urinal will depend on the tee or tees you install before it.

Example: 1x1x1/2 at 2 lavs, then 1x3/4x1/2 to toilet then 3/4" to urinal
__________________
When posting in forums, letting us know your location will help others give better feedback/advice/solutions to your questions
TheEplumber is online now   Reply With Quote
The Following User Says Thank You to TheEplumber For This Useful Post:
gizzygone (11-21-2015)
Old 09-22-2015, 06:25 PM   #9
Member
 
Join Date: Mar 2013
Location: Ohio
Posts: 5,653
Rewards Points: 1,852
Default


Urinal water line size is 3/4 always.
Ghostmaker is offline   Reply With Quote
The Following User Says Thank You to Ghostmaker For This Useful Post:
gizzygone (11-21-2015)
Old 11-18-2015, 09:29 PM   #10
Member
 
Join Date: Jul 2012
Location: Massachusetts
Posts: 389
Rewards Points: 290
Default


Quote:
Originally Posted by Ghostmaker View Post
Urinal water line size is 3/4 always.
Digging this back up again: 3/4" is typically the copper size, but if I go PEX, wouldn't I want 1" due to the smaller ID of PEX?
gizzygone is offline   Reply With Quote
Old 11-18-2015, 09:31 PM   #11
Newbie
 
Join Date: Nov 2015
Posts: 1
Rewards Points: 2
Default


I would also run 1"
carlpainter is offline   Reply With Quote
Old 11-19-2015, 12:37 PM   #12
Plumber
 
TheEplumber's Avatar
 
Join Date: Jul 2010
Location: North Idaho
Posts: 11,384
Rewards Points: 170
Default


1" to the urinal branch. Then 3/4" copper stub out at the urinal
__________________
When posting in forums, letting us know your location will help others give better feedback/advice/solutions to your questions
TheEplumber is online now   Reply With Quote
Old 11-19-2015, 02:47 PM   #13
Member
 
Join Date: Jul 2012
Location: Massachusetts
Posts: 389
Rewards Points: 290
Default


Quote:
Originally Posted by TheEplumber View Post
1" to the urinal branch. Then 3/4" copper stub out at the urinal
Quote:
Originally Posted by carlpainter View Post
I would also run 1"
Sounds like a direct 1" to the urinal is the way to go: do you think if I put the urinal as the first tee, and then continue the line to the toilet and sink I'd be okay? Or should I run 1" direct to the urinal and a separate line for the sink and toilet from the copper main?
gizzygone is offline   Reply With Quote
Old 11-19-2015, 09:16 PM   #14
Plumber
 
TheEplumber's Avatar
 
Join Date: Jul 2010
Location: North Idaho
Posts: 11,384
Rewards Points: 170
Default


You don't need a separate line.
1" will serve the group. You want 1" until the urinal- serve it with 3/4"
__________________
When posting in forums, letting us know your location will help others give better feedback/advice/solutions to your questions
TheEplumber is online now   Reply With Quote
The Following User Says Thank You to TheEplumber For This Useful Post:
gizzygone (11-21-2015)
Old 11-21-2015, 09:29 AM   #15
Member
 
Join Date: Jul 2012
Location: Massachusetts
Posts: 389
Rewards Points: 290
Default


Let's see if this works: Here's a crude schematic if what I'm hearing: is this correct?

Selecting Pex Line size?-image.jpg
gizzygone is offline   Reply With Quote
Sponsored Links
Advertisement
 
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Complete blockage of main line mnp13 Plumbing 9 05-29-2012 10:51 AM
Suction line size kogashuko HVAC 5 07-07-2011 10:27 PM
A blocked water line causing water to loose heat? Snav Plumbing 6 05-07-2010 02:18 PM
Need to run gas line to Tankless Water Heater. anonymouscuban Plumbing 2 04-16-2010 02:56 PM
Wire Size Help-400ft line to pond for fountain brownie47854 Electrical 14 04-22-2007 12:50 PM




Top of Page | View New Posts