Replacing 1/2" copper with PEX - Guidance Please

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three_jeeps

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I am planning to retrofit the ½” copper water lines in my house basement (typical mid 60s suburban home) from the entrance line after the water meter (in the basement) and all the various runs in my basement joists to the hot water tank, stationary tubs, to the vertical risers that supply first floor kitchen sink and second floor bathroom. At this point, I am only going to change the piping in the basement and attack the PEX to the vertical risers. I’ll deal with the in-wall piping at a different time.

I am a fairly competent DIYer and I have some basic questions about doing this retrofit with PEX.
I plan on directly replacing the copper pipe 1 to 1. (I may consider upsizing the diameter from ½” to ¾ o 1” to help with volume delivery.) There are no pressure issues currently.

1. I am interested in using the most common PEX pipe and tooling. In my reading so far, I think PEX-A is the most appropriate over the others. True?

2. Type of fitting is most common/ best? (The most common may not be the best, I’d like to know)
Choices I think are most appropriate:
a) Crimp: PEX Crimp tool and copper crimp rings
b) Clamp: Clamp (Cinch) Tool and Stainless Steel Cinch Clamps
c) Expansion fitting: Uponor (Wirsbo) proPEX

Some of the areas are potentially a tight fit, so an angled tool head or 'mini tool' might be required as well as a straight inline tool - suggestion?

3. Good online supply houses? (pexuniverse?)

I am not concerned about tooling costs or component costs – I’d rather use the right stuff rather than use the ‘cheap stuff’ I’d like Comments/suggestions/guidance from the people who do this for a living and/or have some experience.
Thanks for any help...
J
 
The wirsbo expansion system is far and away the best pex system. The inside diameter is still smaller than copper but the flow restriction is still much less than crimp fittings, so replacing 1/2” with 1/2”shouldn’t mess with your water volume
 
there are a few different methods with pex I use copper rings and crimp them the crimp tools I use are made by mil3 they have been in biz for 30 years its what you can afford and what your comfortable with
 
1/2" PEX tubing has almost twice the pressure loss as 1/2" copper tubing. If replacing lines feeding more than one fixture, 3/4" is the way to go, in my opinion.

Pressure loses due to fittings should not be a big factor if the tubing is installed using minimal fittings.
 
1/2" PEX tubing has almost twice the pressure loss as 1/2" copper tubing. If replacing lines feeding more than one fixture, 3/4" is the way to go, in my opinion.

Pressure loses due to fittings should not be a big factor if the tubing is installed using minimal fittings.

Mainly the case with crimp fittings because your 1/2” (not true 1/2” but close enough) now becomes 3/8”. Expansion systems have fittings the same inside diameter as the pipe so flow isn’t restricted nearly as much.
 
Mainly the case with crimp fittings because your 1/2” (not true 1/2” but close enough) now becomes 3/8”. Expansion systems have fittings the same inside diameter as the pipe so flow isn’t restricted nearly as much.
First off let me make myself clear. I am not trying to say any one is best and /or why, only trying to look at actual factors that affect peoples decisions. One of course being pressure loss values and just how much difference when comparing typical installations.
Do you have any actual pressure loss values for the wirsbo expansion system fittings? I believe they have both metal and plastic fittings, which in itself have different pressure loss values.
Then compare it to the pressure losses of the more restricted non-expansion types?
And then seen just how substantial or negligible it impacts a typical system?
 
I don’t have any chart numbers, I’ve just used them both. I’ve plumbed water distribution in new construction using each system on similar houses and the flow was much better with wirsbo trying to fill a free standing tub. To get the same flow from crimp systems, you gotta take everything up a size as close to the fixture as you can.
 
I am a PEX novice . Only used it once , when we replaced the water line from the meter ( in the alley ) to the house .

The old line was 3/4" copper . I went back with 1" white PEX , because of the smaller internal diameter of fittings ( I had read ) . We used brass PEX " barbs " and the copper crimp rings .

Purchased PEX & fittings locally . Planned to " rent " the crimping tool , but the rental tool did not go to 1" . So I purchased a crimping tool , 1" to 3/8" , at Home Depot . It has made exactly 2 crimps and is laying in my garage , gathering dust .

I had to rent a mini excavator to dig the ditch and again to back fill the ditch ( from Home Depot ) . Rental was quite a bit more than the material .

Wyr
God bless
 
1. I am interested in using the most common PEX pipe and tooling. In my reading so far, I think PEX-A is the most appropriate over the others. True? Pex-B is most common. Pex-A is a bit more flexible and costs about 10% more than Pex-B. Pex-A wll not work with expansion fittings.

2. Type of fitting is most common/ best? (The most common may not be the best, I’d like to know)
a) Crimp: PEX Crimp tool and copper crimp rings
Most common and most available, tools, fittings, and rings


b) Clamp: Clamp (Cinch) Tool and Stainless Steel Cinch Clamps
Don't bother. I suppose they work but why uses them when the copper rings will last forever.

c) Expansion fitting: Uponor (Wirsbo) proPEX
Choice fittings for a lot of contractors. Connections are quick and allow work in tight spaces since you can flex or slide the tubing around after expanding.
Downside: Tool is expensive. (can get generic manual expander for under $200) Uncommon fittings are hard to find! Depot and Lowes do not stock any expansion fittings or tools!



3. Good online supply houses? (pexuniverse?)
Can't remember if I ever ordered from Pex Universe but they seem to have a good selection.
I have used: SupplyHouse, completeplumbingsource.com, Amazon, and eBay


Not sure how much difference the flow issue is between expansion and crimp. A big benefit of pex is that you can pull long runs through and around things with minimal fittings. If you have a 50' run of pex with one fitting at each end, it won't make a difference. If you end up with 10 splices, elbows, etc. in that same run, I think it will make a difference.
 
"Pex-B. Pex-A will not work with expansion fittings."???
Uponor (Wirsbo) proPEX = PEX-A

They certainly make it more confusing than need be!
 
Sorry, that's me typing faster than my brain works.
Pex-A is the only one that works with expansion fittings.
Pex-B DOES NOT work with expansion fittings
 
For what it’s worth....Pex B will work if you are in a bind but you void any warranty of the product. Pex A is the only approved piping for expansion.
 
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