Copper or Pex A/B

[jyl]

Bear with me, I’m not a plumber and I hate plumbing so I’ve studiously avoided learning anything more than how to replace a garbage disposal or a sink and faucet.

My question is, for supply lines, when would you use copper and when would you use pex, and A or B, and why?

[cabmandone]

I'd use pex and I can sweat copper! Why? You can have long runs with less fittings. You can put a distribution manifold in that allows you to isolate if you need to work on a certain branch rather than shutting off the whole system or large parts of it. Pex doesn't care about water quality. Pex expands (probably not a big selling point for your area) if it freezes and has less tendency to burst. The tools to install Pex are relatively cheap. In tight spaces you don't have to worry about catching things on fire because you're sweating fittings. Lots of benefits to pex over copper. I can't think of many benefits of copper vs Pex.

[greglepore]

Agree with Nick. I have pex in my home, installed in aughts without a manifold. I've had manifold systems and they rock.
I've also had homes with issues with pinholing copper from minerals. In fact, the pex here was assembled with junctions that were copper (no one does that anymore) and they're all failing due to mineral issues...
And copper is 10x the price.

[jyl]

So when the plumber comes to pipe the cafe, if he says pex is the way to go, no reason to second guess him? It being a commercial space doesn’t change anything?

[Cajundaddy]

There is no perfect plumbing and I think it depends on your situation. Pex is flexible and expandable so far fewer fittings and far less earthquake or freeze damage prone. The downsides are chafe and rodent damage.

My daughter had a condo built in the 2000s with all pex that ran through the attic. One or more of her neighbors had low cleanliness standards, attracted rats to the attic and over a 6 month infestation she had water raining down from several leaks in the attic. Samples of the leaky sections verified rat chew caused it. With the help of homeowner insurance she had the entire condo replumbed in copper and it solved the problem. It was a major hassle until repairs were completed.

Most of my homes have been copper with very few issues over 40 years. Some time after the 90s earthquake swarm we did develop a leak where wall meets slab in the kitchen. The repair required complete demo of kitchen floor, cabinets, and counter top. This too was mostly covered by insurance and my wife got to pick out new cabinets and countertop which actually pleased her in the long run. It was a month total time for the demo/repair/remodel.

Our current home is all pex with lines run in the walls and crawl space. I see very little exposure or opportunity for rodent damage so I think this was a good choice. Five years in and all is well.

[greglepore]

Yeah, valid point. I had mice access my attic in a prior house and I had a series of ceiling leaks, one on christmas morning, before I figured out what it was. In interior walls its probably a non issue, same with basement ceiling/crawl. If I had unlimited funds I'd run attic pex inside conduit.
As far as commercial space goes, no difference. I'm assuming you're not using a high temp preheater for the dishwasher, or if you are that you'd plumb that with the appropriate material recommended by a plumber as I'm not sure pex is rated for that.

[NY65912]

Having been responsible for purchasing materials when I worked in the plumbing business, I would go with PEX based on price of materials. PEX is like $1 a foot for 1/2" and 1/2" copper is over $4.50 today.

Both have upsides and downsides.

Personally I have never used PEX only copper. But hey, I'm an old dog.

[Bill Douglas]

A friend got his whole house replumbed with copper "because PEX is bad for your health, it releases plastic particles".

I wasn't being horrible, I was just being factual, and explained to him the city water supply coming to your house is all PEX or similar.

[look 171]

I used copper when I remodeled my own home, but pex on all my rentals without issues. Easy, and cheap. I dislike the plastic leeching into drinking water, if there are any? The current house we are working on decided to do copper throughout. We sweated the joints instead having them pressed. didn't really trust the rubber 0-rings.

Yep. rats live to chew on it because its like chocolate to them. Just keep the house tight and no problem, if not, it will get chewed and rain on ya in the middle of the night.

[NY65912]

Look 171. I agree on CT. Personally I would only use copper. Regarding ProPress we have installed thousands of PP joints from 1/2" up to 4" without a single failure. If installed per approved the method PP is a fantastic solution. Our crews were trained by the manufacturers. My company's focus was healthcare, schools, public housing and institutional clients.

I would have no hesitation using PP.

[chrismorse]

I was a contractor for 35 years and started out doing copper. When PEX came out, it was called "Aqua PEX', which used the expansion tools to enlarge the diameter of the "pipe", with a collar on it - which was then slipped onto a barbed fitting - never had a joint fail, except once on a remodel that was running 100 PSI + water pressure.
Aqua PEX is Pex A which uses the expansion tool with a sleeve over the pipe. PEX B, i have no experience with, but i can tell you the parts are not interchangeable - the "B" has a smaller inside diameter and uses a proprietary "Crimp" fitting and tools. My guess is that the B system is a bit faster, because fastening goes more quickly and you don't have to wait for the pipe and collar, (Pex A), to shrink back to its original size/seal pressure tight.
We once replumbed an old farm house with the "Manifold" system and it went quite quickly.
Think about for a minute, which system is likely to have more waste : PEX - 50-100 foot roll, or copper with 10-20 foot sticks??

I still use PEX A cheaper parts and a lot less labor.

Fittings, brass, Fiberglass, or SharkBite??? (all PEX A). SharkBite is faster, but more costly - a lot. I've had no failures/leaks with either fiberglass or brass, but i am still a bit old fashioned and sleep better with brass fittings when concealed in a wall or inaccessible part of the structure.

So far, fingers crossed, I've had no rat chew failures, but i have had a few pinhole copper failures and a few joint leaks.

If the Pex is exposed to potential freeze, I still like to use foam pipe wrap to protect the pipe - I've only had one minor PEX pex freeze leak.

The 12 volt Milwaukee Pex expander is a real Jewell, especially when working under the house,, or tight spaces.

Like all plumbing types, (Pex, PVC, CPVC, Copper, Galvanized), i still like to use canvass fitting bags , "Parachute Bags", sorted by type and pipe diameter, 1/2, 3/4, and 1 inch.

Leaky Chris

[Gogar]

+1 PEX is nice and you can do a fine job if you're handy.

As mentioned if you're doing more than a tiny job just go ahead and buy the tools and skip the SharkBite.

[Brian 162]

All new home construction up here is pex piping. It probably takes half the time, but pex pipe needs more supports installed. It’s probably half the cost. I’m an old school guy, I did nothing but copper plumbing until I retired 11 years ago. I did a couple of pex jobs. It was easier to run long supply lines and not worrying about soldering pipe.

[rwest]

Copper guy here!

I just get so much satisfaction from sweating the fittings.

I have never used PEX and I have a slight concern- slightly more than no concern that whatever chemicals are used to keep it flexible could leach out over time and also harden the lines making breakage easier- NO proof or experience, just my gut. Copper has microbial properties, but likely not much with the quantity of water going through it.

Bottom line is sweating copper together makes me feel like a real man!

[A930Rocket]

I’ve been using PEX in every house I’ve built for companies and my personal houses, the last 25+ years. No problems to date.

When I got transferred to Charleston, the plumber was using CVPC and I had them changed to PEX. It was faster and fewer joints.

[rwest]

Originally Posted by A930Rocket

When I got transferred to Charleston, the plumber was using CVPC and I had them changed to PEX. It was faster and fewer joints.

CVPC is what the devil plumbs houses with. That stuff gets super brittle after 20 some years. My house was pretty much completely done in that junk when I bought it and every time I do a plumbing project, I replace those sections. I just have the bathroom left.

[Bill Douglas]

Here in New Zealand we don't use solder to join copper pipes we braze them. Because I only do plumbing for myself so very low volume of work I use Silfos which is really easy to use with a Mapp gas torch.

[jyl]

I wonder if they can add something to plastic, rubber, vinyl to make it bitter tasting.

[sc_rufctr]

Pex is convenient but I prefer working with copper and avoid crimped connections. Sweating is forever.

[Bill Douglas]

Peter, do you guys solder or braze?

And thanks again for that Bambino knowledge. I still haven't decided what to do.