First time PEX Project - Planning

[hhcibtpaun]

Hey Everyone,

Been here off and on for years. I am about to embark on my largest plumbing project to date . Hoping to get some advice along the way. The project at hand is to replace all the copper piping in my house with PEX A (Expander fittings). The house in question was built in the Mid 1940's and a local plumber told me there is acidic water and many houses in the area have seen pinhole issues. I have most of the house gutted - at least where the plumbing is. So, I decided to replace it all. I watched a few You Tube videos and bought the Milwaukee Expander tool. The house has the following fixtures:

I still need to add lengths of the runs (everything will be home run) and height above meter in the chart above. From resources on this site I calculated 20.5 fixture units with 9 cold and 7 hot manifold connections. Before getting too far into the details, my first concern was the water meter coming into my basement. It looks like it comes in as 3/4, then is necked down to 1/2, then back to 3/4, then back to 1/2 (I think). See image below:

My plan was to run 3/4 PEX from the meter to the manifold. At first I was just going to take out the whole mess around the meter, then started thinking maybe I just leave it alone and upsize the 1/2" a few feet after it leaves the meter. I plan to do most things myself, but if the connections around the meter should be cleaned up, I would get a plumber or talk to the township. I assume they have some claim to the meter.

As I was pondering that I decided to get a pressure reading to baseline everything. So, I bought a SharkBite connector with a pressure gauge. I mounted it about 11 feet away from the meter, then ran a stub with cap out the other end. When I did that I get a pressure reading of 70 PSI.

So, my first few questions.

1. Is the 70 PSI high, or is the fact that I terminated right after the gauge and only have it 11 ft downstream giving me a high reading?
2. Do I get involved with cleaning up the mess of upsizes and downsizes around the meter? My neighbor apparently has the same mess.
3. If I keep the 1/2" coming out of the meter, do I upsize to 3/4" a few feet from the meter and take that to my manifold (maybe 20' away), or do I run 1/2" up to the manifold and then just upsize to 3/4" or 1" depending on what manifold is available? I am looking at something like this for the manifold. The 1" inlet is more readily available than the 3/4" version. Wondering if the upsizing will drop the pressures, or maybe they remain the same.

Thoughts and comments appreciated.

Thanks...Mike

 

[Jeff H Young]

I would replace all the way to the meter tailpiece ( threaded joint just downstream of the union on customer side of union) . 70 psi is close but you don't need a PRV . plenty of pressure a 1 bath home I'd be comfortable running main from meter 3/4"

 

[Sponsor]

 

[hhcibtpaun]

I would replace all the way to the meter tailpiece ( threaded joint just downstream of the union on customer side of union)

Thanks Jeff...Is what I highlighted in yellow what you were talking about?

If so, do I need a check valve? Thinking a check valve, shutoff valve, then a short stub to a 90 and pex fitting. One of my other concerns is the ground wires. I assume if I re-attach them to where they are I should be fine, even though I will be changing to PEX?

 

[Jeff H Young]

You only go to the thread downstream of the ground clamp . Check valve? I don't see it but we don't use them ask your water provider and or city /county plumbing inspector. I'd follow their rules even if it wasn't permitted work. If a check valve is in the main you will need thermal expansion tank . Its possible the check valve is not required (don't know why it is there)

 

[hhcibtpaun]

Thanks. ok, so the green area? There is no check valve. It was just a question if I should add....

Thanks...Mike

 

[Jeff H Young]

Yes that's where I'd begin with the new piping. Ok as for the check valve I see no reason to install one.

 

[hhcibtpaun]

Great, thanks. I will run 3/4" copper, then a 90 to a shutoff valve, then connect my PEX at the outlet of the shutoff. One piece of the puzzle solved. Thanks for all of the advice.

Mike

 

[Jeff H Young]

Might want some support on it .

 

[Terry]

A one bathroom home can have 3/4" copper or poly from the meter.
If using PEX, which has a smaller diameter, it should be 1"

 

[hhcibtpaun]

Good point. I will see if I can support it somehow. Worst case I will run 4' of 3/4" copper up the the joists, then run my pex from there. If I go to the joist I can tie the copper off there.

 

[hhcibtpaun]

A one bathroom home can have 3/4" copper or poly from the meter.
If using PEX, which has a smaller diameter, it should be 1"

Thanks. Currently the house has 1/2" copper from the meter. I never lived there to know if that was acceptable. If I went 1" would I upsize after the meter?

Thanks...Mike

 

[Jeff H Young]

Sure 1 inch will be a bit better to your first manifold 70 psi and such a short run shouldn't be an issue but the 1 inch is better just increase at the first joint. Without question the 1/2 was undersized undersized doesn't mean you'll ever know the difference necessarily but its not up to minimum standard. I thought the need to be 1 inch negligible but agree its a better build . looks better I doubt you'll get more life out of it , pretty typical here to have meter 60, 80 foot from house with an underground 3/4 PVC line and then a small home. with perfect function. not sure how it comes out on paper but 3/4 I'm sure is just about maxed out I probably should have recommended it to go 1 inch

 

[Terry]

Thanks. Currently the house has 1/2" copper from the meter. I never lived there to know if that was acceptable. If I went 1" would I upsize after the meter?

Thanks...Mike

It's about distance and friction loss. You can have a 5/8" or 3/4" meter, both use 3/4" as the output side suppling up to a four bathroom home.
If run with PVC, poly or copper, the 3/4" works for one bath, 1" if running PEX
A two bath home should have 1" and if three bath, 1-1/4" if running PEX.

Water running a few inches loses really nothing. Extend out 80 feet and a lot of volume gets lost due to friction as it passes through. Sort of like drinking a milk shake through a tiny straw.

 

[hhcibtpaun]

Thanks. So, is it still OK to run 3/4" copper for about 4' to get it where I can attach to the joists, then start my run of 1" pex for 20' or 25'? As it turns out the PEX manifold I was going to use is available in 1" and backordered in 3/4".

I assume it is OK for 1/2" pex to all my fixtures? Maybe I would run the 1" pex to my HWH (electric).

Thanks...Mike

 

[Jeff H Young]

1 inch

 

[hhcibtpaun]

Folks,

It's been awhile, but I may actually be starting my PEX project. I am starting to make my shopping list and had a question about valves for the toilet, vanity and Kitchen sink.

I will be using the Hold Rite stub out Kits for most things. I will use PEX, instead of the copper stub outs (although I think many of you go that route). I am paranoid about the acidic water.

So with these I will have pex sticking out of my wall and I was planning to buy the propex Angled Stop valves.

While reading through some other threads I read about folks using Compression Angle Stop Valves on PEX. I know people use them on copper, so it piqued my interest.

With the ProPex valve my concern is if I ever have to replace a valve. From what I understand I would need to cut tubing to replace a valve. I guess I could leave a little extra tubing in the wall to allow for a tug at a later date. With the expansion valves, I think I would just add a new one? Or would the tubing be messed up from the compression.

I could be way overthinking all of this, but would the recommendation be for the compression valves or just the expansion valves. Is one connection more prone to leaking, or once the connection is made and not leaking, it is just a valve failure that can be the issue?

Since this is my first PEX job, I am trying to make all connections as visible as possible, in case I need to edit.

TIA...Mike

 

[Weekend Handyman]

Folks,

It's been awhile, but I may actually be starting my PEX project. I am starting to make my shopping list and had a question about valves for the toilet, vanity and Kitchen sink.

I will be using the Hold Rite stub out Kits for most things. I will use PEX, instead of the copper stub outs (although I think many of you go that route). I am paranoid about the acidic water.

View attachment 90156

So with these I will have pex sticking out of my wall and I was planning to buy the propex Angled Stop valves.

View attachment 90157

While reading through some other threads I read about folks using Compression Angle Stop Valves on PEX. I know people use them on copper, so it piqued my interest.

View attachment 90158

With the ProPex valve my concern is if I ever have to replace a valve. From what I understand I would need to cut tubing to replace a valve. I guess I could leave a little extra tubing in the wall to allow for a tug at a later date. With the expansion valves, I think I would just add a new one? Or would the tubing be messed up from the compression.

I could be way overthinking all of this, but would the recommendation be for the compression valves or just the expansion valves.

Since this is my first PEX job, I am trying to make all connections as visible as possible, in case I need to edit.

TIA...Mike

I am not a plumber.

I just crimp on my angle stops.

I would anticipate your 1/4 turn ball valves will last a long time ... that is what I am betting on anyway.

 

[hhcibtpaun]

I just crimp on my angle stops.
I would anticipate your 1/4 turn ball valves will last a long time ... that is what I am betting on anyway.

Thanks.

I thought of another possibility. Since I have a tendency to overtighten things, there is an outside chance I could overtighten compression fittings . Maybe I just stub out like 3" or 4" from the wall and use the expansion connection, then if in the future a valve needs to be replaced I can cut off the 2", then replace the valve with maybe a compression fitting...at that point it may be my son's problem....

Thanks....Mike

 

[Weekend Handyman]

If you have the space, that could work. Check your cabinet to seem how much room you have. My wife likes the IKEA stuff with the sliding drawers. For those, the angle stops have to be very close to the wall. Also, you will want to makes sure you cover up any exposed pex to avoid UV exposure.

You could also consider sharkbite for the angles stops. I am not sure if you would have to cut back the PEX or not to if you ever have to change out a sharkbite angles stop.