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Dean
Copper vs Pex vs Cpvc

We're in the design stages of having a new house built. We're getting conflicting advise on what type of pipe to use. There seems to be positive and negative for all 3 types. If you were building a new house what would you use?

1. PEX - Positives: ease of installation, cost, ability to run each line individually and shut off that line if necessary. Negatives: Not a "soldered/glued" connection, connection can work loose. Is this poly butalane all over again? Given time will PEX stand up over time?

2. Cpvc - Positives - glued connection, connection won't work loose. Cost is relatively cheap. Negatives - increased installation costs, longevity. My current plumber says that when he has gone in to replace a section of Cpvc in homes as new as 2 years old, when he goes to cut the pipe the pipe crumbles in his hand. He said this has happened to him several times.

3. Copper - Positives - soldered connections - long lasting. Negatives - High cost of materials, higher cost of installation, the builders in this area don't have plumbers used to dealing with copper, so not sure how good the installation would be. I've also been told that copper can develop pin hole leaks if water has a high acid content.

So what you would you have installed?

Cougars1996
Re: Copper vs Pex vs Cpvc

PEX. I think the issue of long life is pretty much resolved as it has been in use for a while outside of the USA. I think the connections are pretty well self-sealing even if they are not soldered. I have had it in my addition for 5 years now, with some connections inside walls, with no problems at all.

Good Luck!

dj1
Re: Copper vs Pex vs Cpvc

I always choose copper.

HOWEVER, because your local plumbers don't work with copper, AND because copper prices have reached the moon, I suggest you go with PEX too.

johnjh2o
Re: Copper vs Pex vs Cpvc

You didn't say what type of construction your home would be. Will the lines be in a basement or under a slab? If there in a basement or crawl space, then mt first choice is copper, followed by PEX then CPVC. If the plumbers in your area are not able to deal with copper then there not plumbers and I would me very leery of anything they do. I have also seen CPVC get very brittle after time. PEX has also had some problems with splitting. But to be fair these failures were do to one manufacturer that is no longer making pipe.

John

dj1
Re: Copper vs Pex vs Cpvc

Let me just add this:

You mentioned pin holes in copper. Well they do happen due to minerals, sediments and other metals and elements in the water. However, if you use the recommended type L copper, which is a thicker copper, the chance for pin holes goes down significantly.
Costs a little more, yet lasts a lot longer.

Dean
Re: Copper vs Pex vs Cpvc

Additional information - This home is going to be on a crawl space.

johnjh2o
Re: Copper vs Pex vs Cpvc
drhcrou wrote:

Additional information - This home is going to be on a crawl space.

I would go with copper but if cost is a main consideration PEX should give you good service. One other thing to consider is the ID of PEX is smaller then copper so sizing becomes a big concern. On a average size home 3/4" mains with 1/2" branches to each fixture should be fine. (avoid putting two fixtures on 1/2")

John

JerryB
Re: Copper vs Pex vs Cpvc

PEX.

We made a huge mistake and moved from Colorado to TX in 2005 (moved back to CO 1yr later)and built our own 5,400s/f home with 3 1/2 baths, kitchen, laundry, mud room, ice maker, RO water filter. I plumbed the house myself using PEX with manifold. Blue PEX for cold, red PEX for hot.

So much easier and cheaper (even in 2005 dollars) than copper.

I have also used copper and like how nice and straight copper runs can be, but the ease, cost and reduced effort of PEX is a no brainer.

Fencepost
Re: Copper vs Pex vs Cpvc

There are three topics to avoid in mixed company: politics, religion, and types of pipe. :eek:

That said, my first preference is PEX, followed by copper, followed by CPVC. I don't like CPVC because it does get brittle (crumble in your hand is an exaggeration). Copper may have issues with certain types of water. PEX will last forever as long as its not exposed to sunlight (UV), and the pipe is freeze resistant.

Note that each manufacturer of PEX has their own fittings, and will only warranty the installation when the fittings and pipe are their own brand, and installed according to their instructions. At least one brand provides different lengths of warranty depending on whether or not the installer has received manufacturer certification. In all cases it requires special tools or "shark bite" type fittings, and for a large job buying the special tools will be cheaper than using shark-bites.

They are called "shark bite" fittings 'cause that's what they do to your wallet.

FriendlyHomeServices
Re: Copper vs Pex vs Cpvc

In my experience, pinholes in copper pipe are caused by copper touching metal in the ground or by touching rock or concrete, where the vibration of water running through the pipe over time rubs a hole in the pipe at the spot that is in contact with the offending object. Also, older homes used a Main Electrical Ground to Copper Piping instead of a Grounding Rod, which can also cause issues when a circuit in the house "goes to ground" and can hasten the forming of pinholes. Mineral deposits will generally coat the interior walls of the pipe and not by itself corrode a pinhole through copper.

PEX with a manifold system is the most cost effective in my mind with what is available, using Crimp Fittings made of Brass with Stainless Steel Crimp Rings. Using a Hot & Cold Manifold with PEX, there is no need for individual stops or shut-off valves at each fixture, providing a cleaner look. The Plumber should have a guage to test crimps through the job to make sure the Crimping Tool is calibrated properly - big problem with Quest or Polybutylene Tubing from the 1980's - Guys Plumb in a whole subdivision and never calibrate their Crimping Tool, progressively leaving "loose" connections that can blow out over time. Also Quest/PB fittings were made of the same material and easily cracked and broke under extended stress of any kind...

CPVC is complete garbage in my opinion - restricts flow and must be Solvent Welded properly, or fittings will blow loose...

I hope this helps...

Friendly Home Services Baton Rouge...

perchinonlakeerie
Re: Copper vs Pex vs Cpvc

Ayn plumber that is any good can and will work with copper. That being said L coopper is the only way to go unless it is under a slab in which case k copper should be used. I have seen multiple jobs where cpvc has fail within a few years, and have seen pex fiitings fail and pex crimp rings fail. 99% of our new work jobs are copper. I tear out plastic and steel almost daily and replace them all with copper. It just makes for a better quality job and can add resale value.

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