How to Build a PEX Manifold: A Step-by-Step Guide
**Our honesty policy: This post may contain affiliate links and I may be compensated if you make a purchase at no extra cost to you. Some are, some aren't--I do some comparison shopping. The important thing is you will know exactly what we are talking about. Drop a note/comment if you have any questions on the products as these are materials and tools we use on our own projects.
That whole house Uponor PEX-a manifold you see there is real:
Really solid…
Really water leak tested…
Really shiny…
And, most importantly, really done!
The failing rolled copper trunk and branch system previously servicing this house is now replaced with an whole house Uponor PEX-A manifold system. The Uponor manifold is the best of all plumbing options together: all the benefits of Uponor PEX-a, as seen in this last post, along with the reliability of a copper manifold.
The steps below outline how my husband constructed* this Uponor manifold on a current rebuild.
**Warning** This is A LOT of information that pretty much outlines every last detail of the process. If at any point you say, “I’m out! An entire house PEX manifold is not for me!”, it is still possible. Check out the offer at the end.
**Also, just a reminder you can click on images to get a larger picture, if you want a closer look.
Step 0a. Decide you want a manifold system with separate home runs to each fixture (or some other great reason as discussed here: Advantages of a Plumbing Manifold System)
Step 0b. Decide you want to use Uponor (as discussed here: Why Choose an Uponor Manifold System).
Step 0c. Have some mad soldering skilz.
AKA good enough to create leak free joints.
Steps 1-5. Half the work is planning.
Making sure you have the right number of hot and cold lines as well as the proper sizes. It’s not just about the number of sinks, laundry and other water loving appliances (see the checklist at the bottom of this post for any you may have overlooked**)–you also have to consider exterior faucets in you calculations as well.
In addition, you have to plan how you want to attach the manifold to the wall / cabinet / some sort of housing. We chose to use 1” copper plated bell hangers.
Once you build a PEX manifold and install it in place you don’t want to think about changes or expanding later. We suggest adding an extra line for future changes. The manifold has two extra lines: one 1/2″ on the cold side and another 3/4″ on the hot side, both which run up into the attic and are capped…waiting patiently, perhaps never used, but there, if needed. For completeness, they are not charged with water either. Just leave the valve in the off position.
Here are two related posts that are very much part of the planning phase:
How to Design a PEX Water Manifold for an Entire House
Sanity Saving PEX Manifold Installation Tips
Step 6. Double check your numbers again.
You don’t want to be waiting on ordering / running to the plumbing supply for one last piece later…
Step 7. Place the order.
Uponor is not off the shelf at a big box store. You’ll find it at your local plumbing supply or online. We have had great experiences with supplyhouse.com.
Here is the pick list for everything for the final manifold in this post (this includes the one minor modification explained in Step 9, Consideration #5).
1 – 1″ x 4′ Type M Straight Copper Pipe
1 – 1″ x 2′ Type M Straight Copper Pipe
1 – 3/4″ x 3′ Type M Straight Copper Pipe
1 – 1″ Copper Cap
1 – 1″ FTG x Copper 90° Street Elbow
4 – 1″ x 1″ x 3/4″ CxCxC Reducing Tee
2 – 1″ x 3/4″ x 1″ CxCxC Reducing Tee
1 – 3/4″ Sweat Full Port Ball Valve w/ T-Handle (Lead Free)
1 – 1″ Sweat Full Port Ball Valve w/ T-Handle (Lead Free)
2 – 3/4″ ProPEX x 3/4″ Copper Pipe Adapter (Lead Free Brass)
1 – 3/4″ ProPEX x 1″ Copper Fitting Adapter (Lead Free Brass)
1 – 1″ Copper Manifold w/ LF Brass 1/2″ ProPEX Ball Valve, 8 Outlets (Lead Free Brass)
1 – 1″ Copper Manifold w/ 1/2″ ProPEX Ball Valve, 12 Outlets (Lead Free Brass)
4 – 3/4″ ProPEX x 3/4″ Copper Adapter Brass Ball Valve, Large Bore (Lead Free)
6 – Bell Hangers
At this stage you’ll also need a tubing cutter.
Step 8. Verify you have everything on hand and admire how shiny everything looks.
Step 9. Start measuring out how everything is going to fit together.
You might want to start with this step before placing the order, but really, as long as you have the master design (as you can see there is a ‘D’ shape in the cold supply in the first picture, along with a general sense of the size of the manifold), you can just buy a decent length of copper along with all the couplings, shutoffs, etc. and start. Then again, if you are replicating the manifold in this post (by all means!), you can just buy everything in the pick list and know you are covered! 😉
Verify the depth of the stops on each coupling. Once you know these measurements you can start mapping out the lengths between each piece.
…you get the idea.
There are a couple functional and aesthetic thoughts to take into account during this planning process. Yes, aesthetic is a real consideration. We are not spending all this time, energy and money on a sloppy plan. We want you to show this off with pride, as you should!
#1. Consider any future changes or repairs.
Sure, we could build this with the minimum pieces.
However, attaching the shutoff directly to the manifold means if anything goes wrong, you are guaranteed to touch the two major pieces of your whole house manifold.
Minimizing the affected parts of the manifold seems like a good way to prevent other problems by separating them with cheaper, expendable straight copper pipe.
This is the same reason an additional piece of copper pipe is attached on the end of the hot line instead of just capping the end of the Uponor manifold.
#2. Remember this manifold will be attached somehow.
Whether you use a bell hanger, like we did, or another method, keep in mind where they will be placed and how much space is needed.
In our case, one bell hanger needed to go on the bottom of the cold water loop where the ¾” lines jump off the manifold. Working with a ¾” ball valve and one end of the 1″ straight copper, you shove one end of the copper in the ball valve.
Next, place the bell hanger on the copper and mark where it will attach, leaving enough space for solder to pool between the copper and ball valve. The bell hanger should be mounted so it can be clear of the joints–flat against the pipe.
While you only need one bell hanger in this area, you can maintain this spacing between all three ¾” ball valves for aesthetic consistency.
The added bonus of this methodology? Once you have the measurement you can apply it to the rest without stopping! You can get in a groove and cut all three pieces needed for the four ¾” ball valves at once.
This same methodology was applied on the hot and cold water shutoffs as well. They are on opposite ends of the manifold cabinet, but they match–my husband went for aesthetically pleasing–not just functional.
#3: Maintain enough clearance for all shutoffs.
If a shutoff is in an open position, you don’t account for the swing, then you attach it with the least possible pieces, you find out too late that you can’t shut off the water later.
#4: Maintain enough clearance for all couplings for future maintenance.
If something needs to be changed or fixed later you don’t want to be cramming your hand in too small of a space. Give yourself some room!
#5 You don’t want pieces too far or too close.
Too close and your soldering could damage the shutoffs. Too far and your manifold could take up the entire wall.
Once you see it all together you might make some adjustments. For example, on the first round of design the expectation was to have the cold water supply come up from below the manifold cabinet. However, once it was all laid out the reaction was something like, “HOLY SHIT, BATMAN, THIS IS HUGE!”
Let’s take a moment here.
This manifold looks cute and pretty because it is a small picture on your phone or computer monitor. This is especially true if you have a traditional trunk and branch system hidden within the walls of your house.
In person, this thing is HUGE (but agreed on the pretty part!).
Let’s say you are 5’ 9”, like me on my volleyball roster. If we are 69” and the manifold, without a supply line going in, is 51”, we’re looking at something that comes just below our shoulders.
No, I’m not putting a photo of perspective here because it loses the exciting-big-finish-conclusion photo. You can scroll down quick to spoil the surprise if you so desire. 😉
Once the realization of just how tall the manifold was actually going to be hit, there were two immediate problems:
- The size of the cabinet box
- The point of entry for water was in question.
A bigger box than expected box is doable. However, if you have a standard eight foot wall and the manifold is already at 51 inches, you realize you still need to add gap in at the top and bottom as well as space to service the incoming line–you are looking at something closer to six feet! This only leaves two feet for an incoming water line to loop or curve to the box, if the box is placed all the way against the top of the stud framing.
So a field change took place and an additional 90 degree elbow and an extra ¾” copper length solved that problem. Now the box is significantly smaller and the space below the hot water line is not just wasted space, but a serviceable space for the cold water supply line.
Step 10: Gather all the tools and materials needed to sweat the Uponor manifold together.
Here is the list as shown in the picture above:
- Bernzomatic TS8000KC Premium Torch Kit
- Oatey Plumbing Solder Kit
- Oatey Safe Flo (Lead Free) Solder
- Oatey Sanding Cloth
- Plumbers 4 in 1 Pipe Cleaning Tool
- Deburring Pipe and Depth Gauge Tool
Step 11. Sand all male and female mating surfaces.
It is very important to properly prepare the surfaces you wish to solder together. They need to be free of burrs, dirt and oil in order to have a tight fit. Sanding aids in this process combined with wiping off the sanded surfaces. The added benefit of sanding created tiny lines for your soldering flux to fill and then pull your solder into when heated. This creates greater surface area for the solder to adhere to and create and air/ water tight joint.
Result = Leak free joint. (see Step 15 to verify)
Step 12. Dry fit
All valves should be in alignment so when it comes to soldering the assembly it is on straight.
The main shutoff has to be 90 degrees from the manifold so there is clearance to turn.
Once the Uponor manifold is dry fit in place, mark each connection on both sides with a Sharpie line.
Step 13. Apply flux to every last joint you’ll be soldering together.
Once everything is marked, take everything apart, keeping it in order.
Brush the water soluble flux on both sides (male and female) on the joint that is about to be made.
Step 14. Time to solder!
Elevate the entire assembly so you have space to go down the piece assembly line style. It doesn’t have to be anything fancy–you just want to make sure you can see everything going on.
Make sure all valves are open so smoke and heat can escape.
Heat, solder, heat, solder… No pictures of that–you gotta be moving!
Heat female sides of the joints working your way down the assembly, soldering it together.
Keep a very damp rag on hand to help cool the parts once the sweating is complete.
Step 15. Pressure/ leak test your system.
Get a pressure test gauge. Shut all valves except on the end you choose to connect your test gauge to. Then get the test gauge connected and fill the manifold with air (do not exceed 100 psi). Hold for 2 hours. If your manifold does not lose pressure, then depressurize and go forward. If not, then refill with air and spray your joints with a soapy water solution to locate leaks. Repair as needed, then retest.
This was performed with the help of a master plumber and his equipment for this job, but we are ready for future ones, now.
Here is a DIY kit list to have your own:
1 – Jones Stephens G64100 100 PSI Gas Test Gauge Assembly
1 – 3/4″ ProPEX x 3/4″ NPT Male Adapter (Lead Free Brass)
1 – EZ-FLO 50021 Teflon Pipe Thread Tape
2 – 3/4″ ProPEX Ring with Stop
1 – Small length of scrap 3/4″ PEX-a
1 – bicycle pump
Step 16. Final Sand/ Clean/ Polish.
Time to get the grime, soot, heat marks, and excess from the soldering and handling the manifold fabrication. Break out your sanding cloth, some terry towels, and perhaps some Brass-O. With some good elbow grease and a bit of a buzz from Brass-O fumes, the manifold looks like a saxophone ready for proud display!
Step 17. Build a housing cabinet.
See an upcoming post…
You can skip this step if you plan on installing your manifold inside of an unfinished basement or something similar. You don’t see artwork like this everyday and it is worthy of showing off. This is especially true if you do it yourself!
Step 18. Install the housing cabinet.
When installing, you’ll want to make sure the frame of the box will be flush with the drywall.
The cabinet was dry fit in place to ensure all lines were long enough and the manifold was at a good height.
Once the final height is determined, install blocking to help carry the weight of the cabinet and manifold.
Step 19. Drill holes.
We recommend using Forstner type bits. This will make for cleaner hole than a generic spade bit.
Please note: Drill your holes-1/8″-1/4″ larger than the outer diameter of the PEX pipe. This will allow for easier threading. In single penetrations through studs, this gap allows the installation of isolators to hold the pipe in place preventing slipping and possible damage from handling.
Step 20. Connect the pre-run PEX.
All PEX lines should be secured in place before this step. You absolutely do not want any surprises with a run being juuuust too short.
Consider the order of your lines. You can go all out and match the hot and cold lines between the hot and cold manifolds. You definitely want to label them!
Once all plumbing is ordered and labelled, slip on those pex rings on the pipe runs inside of your “jewelry box” and use that awesome Milwaukee ProPEX expansion tool (or consider the DeWALT 20V MAX PEX Expansion Tool if you are already invested in the DeWALT family of tools–keep in mind this link is only for the tool and not the batteries so you can save some)!
Stretch. Attach. Wait. Repeat until done!
After all of your connections are made, install your bell hangers and secure the manifold in place.
Step 21. Take a picture of your PEX manifold.
Step 22. Take a badass picture next to your handiwork.
Step 23. Take a happy picture next to your handiwork.
Step 24. Drink a glass of water from your shiny new PEX manifold.
Step 25. Have a beer float to celebrate!
As you can see, there is a lot of thought, precision, love, and care that goes into each and every copper manifold like this. By choosing Uponor PEX-a and a copper manifold system you have a reliable, easily serviced system for years to come…as well as a functional masterpiece!
Step 26. Share your manifold experience with us!
If you have one of these or you get inspired by this, we’d love to hear from you!
Feel free to ask questions in the comment section below. We’ve had a couple questions sent through the contact page that have even generated a couple follow on posts (listed below).
Did you end up building your own manifold? We’d love to give you a virtual high five and learn from your experience too!
Too many steps? Not feeling 100% on all that soldering? Go through steps 1-5 and send us your order. We will work with you to create your custom manifold, which will be fully leak tested by a master plumber prior to shipment. (taking orders for August 2021)
Still on the fence if you want to build a PEX manifold (and honestly, even if you aren’t because there is some good advice there!)? Check out these posts to read about more manifold goodness:
- Sanity Saving PEX Manifold Installation Tips <– another must-read if you are still in plumbing planning stages.
- How to Design a PEX Water Manifold for an Entire House <– if you are curious about the connections in this manifold there is a diagram with all outlets labelled.
- Advantages of a Plumbing Manifold System
- Why Choose an Uponor Manifold System
- How to Install a Hose Bibb with a PEX Maintenance Loop <– while not manifold related, something to plan for while laying out your PEX home runs. Make your life easier when you have to maintain your hose bibb.
*The manifold design was inspired by a review on the manifold on SupplyHouse. We can’t give proper credit or reach out since reviews are anonymous.
**Supply plumbing checklist–you don’t want anything to get accidentally missed:
Kitchen sink
Dishwasher
Refrigerator ice/water line
Pot filler
Bathroom sink
Bar sink
Toilet
Shower
Bathtub
Heated floors
Heated towel racks
Washing machine
Water heater
Water softener
Consider these with care if you plan / ever even slightly consider adding a water softener:
Outside spigots
Outside kitchen sink
Outside shower
Utility sink
Pool
Sprinkler System