Hi,
I’m installing a new water supply line to the house and was wondering if the high pressure rated pvc is the way to go as opposed to galvanized. Any thoughts, comments on this? I do have to connect to a galvanized section which runs from the water meter under the sidewalk.
Seems to me that pvc is better since it won’t corrode.
Thanks in advance.
Jon
Replies
Yep... forget galvinized... it is crap compared to the stuff they put in 30 years ago...
I'm not a plumber but I have Installed, broken, repaired and snaked more pipe than anyone IMHO should have to without getting a regular paycheck from the trade. This combined with some research I did years ago in connection to installing plumbing in my own home have biased me toward PVC in most cases. I have installed rigid steel conduit. While this is not plumbing many of the tools and techniques are similar.
- PVC is relatively easy to install and repair with tools you probably have on hand. No expensive dies, taps, drivers, cutters, reamers and tripod necessary.
- PVC seems more resistant to freezing. It doesn't freeze much here so your mileage may vary on this.
- Corrosion, galvanic or otherwise, and drain cleaners don't damage PVC like they can steel. PVC can be damaged with some solvents.
- The internal resistance of PVC is lower. Allowing water, drain or supply, to flow easier and you to use, fairly rarely, smaller pipes and get the same flow rates.
- PVC insulates the water flow so you get hot water at the tap a little faster.
- I have been told and it seems reasonable that PVC is more resistant to and tolerant of water hammer. A proper system shouldn't have excessive water hammer but not all systems are proper.
- Galvanized steel is more resistant to crushing when run under a driveway or similar situation. You can get much the same effect with PVC by sleeving the PVC with steel under the offending roadway.
- Steel is more resistant to puncture by stray nails and screws.
- Iron drain lines are quieter.
- After a house fire, the house burned down, I have seen large portions of the galvanized steel piping still standing and working. :)
As you can see I like PVC better than steel. I don't know, more than the little I have read, about the newer plastic systems like PEX, etc.
With a plumbing contractor we ran a wirsbo(PEX) main into a small commercial building last week. No joints, unions, elbows etc. in a nonlinear path to the building. This was the way to go. You don't need near as big a trench if all you have to do is lay pipe with no joints.
My vote Wirsbo
joe d
Galvanized is not allowed here for water lines anymore (as per code).
That ought to tell ya a lot.James DuHamel
J & M Home Maintenance Service
"Southeast Texas"
Your post scares me big time. For as much pipe as you claim to have worked with your ignorance on the subject is blaring.
Sorry if I am offending you. That is not my point... but rather to speak up for the benefit of others who might read this.
I probably should have clarified a bit, this is just a new supply to the house, the interior supply lines are all copper. I've been told you can use copper for the supply as well (if you want to spend the money). Any thoughts on this? It seems not worth the price.
So when you refer to PEX, is that what I'm calling high pressure pvc? Do they sell it at retail supply houses (HD, Lowes)?
I'm located in Atlanta and the pipe will be buried a little more than a foot down and will be beneath a gravel/paver walkway I'm colocating it in the same trench with the new underground electrical which will be at a depth of 2.5 feet and housed in pvc.
I will have to connect it to an existing galvanized pipe which runs underneath the sidewalk to the meter (unless I can change the water company's mind about replacing it without it leaking presently). Can I use those PVC compression fittings to make the connection or is there a better way.
Thanks again for all the input.
Jon
PVC=polyvinychloride does not equal PEX= crosslinked-polyethlene
The box stores in my area are not marketing viable PEX systems. Plumbing wholesalers sell PEX systems, the brand name Wirsbo seems to be the favorite.
I recommend you run a new piece all the way to the meter. The pipe all the way to the output side of the meter is your responibility. It probably will be possible to fish a new pipe to the meter. Of course you can just leave that piece of galvy in for a future repair. Job security as it were.
joe d
maybe your water chemistry is different in your part of the country, but every part of the country that I've ever been to (mostly in the North) gets red rust from galvanized water pipes. Maybe it takes 20 or 30 years to get started, but when it does you've got 'uncleanable red stains' on your sinks and toilets (you can clean them but they come right back).
Why oh why oh why is anyone still installing domestic galvanized water supply?!?!?!?
Copper or PEX is longer lasting, less stain causing and less likely to get filled up with mineral deposits over time (reduced flow). Also less likely to add that awful iron flavor to your drinking water.
Then again, maybe there's some reason why these things don't occur in Atlanta or something...?
I went with type K copper from the meter to the house. Here in LA, K is required underground, L is used in the house, and M only for smitty pan and relief valve drains. PVC is nice for watering the lawn with a sprinkler system. The one thing I like galvanized pipe for (1" works well) is in clothes closets, to hang the hangers on. It's a lot stiffer than the same size wood bar.
-- J.S.
Isn't PE (polyethalene) approved for exterior service lines. I think that would be a good option here.
The observations I have made have been from personal experience, observation and conversations with plumbers on jobs and independent study of several manuals on the subject and a copy of the UPC bought at a used book sale. I am not a plumber nor have I claimed to be. I'm trained in electrical work but for lack of willingness in this area I sometimes act as carpenter, plumber and any number of other trades. In these other trades I mostly work for friends, neighbors and family. Seldom do I charge more than my cost of materials and gas money. These things I do for the love of the work and an opportunity to learn more.
Those subjects I am not trained in I go out of my way to read up on and pump more knowledgeable individuals, inspectors have been particularly helpful in pointing me to sources, for information needed to do the jobs and do them right. Right as determined by the inspectors and experts in these fields. Most tradesmen, with the exception of yourself and a very few others, seemed more than happy to explain their work and the logic behind their work.
If you have a specific information on any particular point/s I have made cite the text and give me an alternative point of view. While I'm really not offended by you saying I'm wrong, it wouldn't be the first time, I do take umbrage at the broad attack without evidence or specifics. If you know better, or think you know better, state your point of view. Your post adds nothing to help the original poster other than to say that you are talented enough to post a cheap shot.
I will reply in detail later. Since you asked it is the least I can do. Did not mean to be condecending. Sorry if it came across that way. As I recall I was in a hurry that day.
WHW and Forlorn One: You both seem to add value to the forum. Now kiss and make up. I did question 4LORN1's assertions that PVC is better than galv at freezing. PVC gets quite brittle at moderately low temps. A decent alloy's ductile brittle point is well below 32F.
Similarly, I suspect that glav is better at water hammer than PVC. I can beat on metal long than on plastic before failure. Of course, better yet to install either with proper backstops and avoiding very long straight runs.
Otherwise, I agree with your points.
David Thomas Overlooking Cook Inlet in Kenai, Alaska
Speaking of long runs, it's about 65 feet from the water meter to the house. Is there any standard practice for check valves every so many feet to prevent hammer? Should I put one in the section underground?
In my case, I think I'll go with the PVC as the location will provide easy access to it should it ever fail and the cost is far less than copper or galv.
Have you guys had experience with connecting directly to the water meter? My utility company here seems to not know for sure if it's ok. I should think that they would want to make that connection to the meter, but they said it was technically my side, even though it's under the sidewalk? Should I call someone else from the city to get better info? I know that sounds ludicrous??
Thanks again.
Jon
Um, check valves don't prevent water hammer. They just stop the water if it ever tries to go back where it came from.
Water hammer happens when the flow of water is stopped suddenly, by closing a valve or faucet quickly. The water in your pipes is heavy, and when the faucet is on full blast, it moves fairly fast. If the faucet slams shut, that moving weight has to stop instantly. It's sort of like having a heavy freight train speeding thru a tunnel, only to find that the far end has collapsed. If you have the problem, what you need are water hammer arrestors near the ends of the runs. They consist of a chamber with a rubber diaphragm separating it into two parts. One side contains trapped air, and the other is connected to the water. When the water has to be stopped, it compresses the air in the chamber, sort of like a spring,. In fact, it's like the big springs in the bottom of an elevator shaft.
-- J.S.
I will ask again. Isn't PE approved for burried service lines?
If so I think that it would be much better than PVC.
In most areas yes... and it is my preferred service line piping material. But it is not readily available to most DIYers. Sorry for not answering before.
I am talking about the black that works with the barb fittings.
Around here is is available in hardware and farm supply stores along with HD and Lowes.
I think that stuff is junk. It does not hold up nearly as well as schedule 40 PVC in most conditions. But am curious why you think it would be better
Ok, let me post one more thing. Thanks for correcting me on the water hammer, I didn't think it was the sudden stop that created the hammer, but the rebound. Seems I read somewhere that check valves would reduce the distance the water could rebound etc.. but you are right, the arrestor is the thing to do.
The maintenance guy at work tried to convince me to go with copper pipes. For a 3/4" line, it really wouldn't add too much to the cost. I have a contractor friend who can procure any of the PE materials which might not be at retail outlets. So could you give me the why's and why nots of running copper? My concern is the flexibility, I've seen it break under stress at the joints. But I need feedback. Thanks again.
Jon
The pro for copper is that it's been used for plumbing for decades, and we know that it lasts a long time. The con is that it costs more than any other option.
As for stress, what stress would there be on your buried line? Out here we get earthquakes, we have expansive soils, but no frost heaving. Which do you have? You can backfill with pea gravel around the pipe, which allows for a tiny amount of movement to take the stress off the pipe.
The other issue I see is that you're putting the whole house on the far end of 65 feet of 3/4" pipe. If you don't have a whale of a lot of pressure, you're going to wait a while to fill a bath tub. If you do have a lot of pressure, you'll have water running very fast thru that little pipe, which accelerates erosion and reduces its life. I went with 1 1/2" copper.
-- J.S.
Hmm, maybe I should go ahead and excavate under the sidewalk and get to that meter and see what the pipe fitting size is. Are they normally 1.25"? Thanks for the tip!
Jon
There should be some sort of access for reading the meter, usually a cover that flips up in a concrete vault lid. If you pull the whole lid up, you should fairly easily be able to clean out the crud and spiders and get a look at what comes out of the meter. On mine it's one inch, the DWP even calls it "one inch service" on my bill. I stepped up to inch and a half right after the meter.
Check Taunton's "Code Check: Plumbing" book for how to size the pipe. The size you'll get that way is the minimum that code allows, bigger is better. But it's a diminishing returns kind of thing, so going a whole lot bigger isn't cost effective. In addition to lasting longer, larger pipes run quieter because the water goes slower. (Not that you'll hear the underground line, but it's good to know for plumbing inside the house.)
-- J.S.
Edited 4/12/2002 5:30:45 PM ET by JOHN_SPRUNG
Jonbyrd: Why not do your own work under the sidewalk? It is typically on your land. Land you pay taxes on, a sidewalk you have to keep maintained and about which you could be sued if someone trips on it.
John: Correct on the water hammer. Shock absorbing arrestors, shorter runs (offset in the the middle), and securing to good backstops (like poured concrete) all help.
I also wonder about 1" service piping. It's only money (and not a lot in any piping material). But poor water pressure when you're in the shower is a pain. I've got 1.25 to my own place.
Bill and WHW: I distrust the thin black stuff from HD also. Is it PE or PB? The thick PE that the plumbing supplers make up for you is great. All one run, no joints, adapted to straight or 90 degree metal riser with MPT.
Jonbyrd: Almost all residential meters are "5/8-inch meters" which isn't a pipe size, but a measure of the meter's volumetric capacity. They have ¾" pipe threads on them. You could use ¾" pipe for your service line but 1" would be better if your pressure is ever margainal. In that case just add a ¾ x 1" brass bell reducer.
David Thomas Overlooking Cook Inlet in Kenai, Alaska
Dave
The stuff is PE. Here is a link to one brand.
http://www.charterplastics.com/water.html#PE 3408 Black
It comes in ratings from 80 to 250 psi. Lowes has the 100 and 160 and it might also have the 200, but it has been a while since I looked at it.
The wall thickness for 1" pipe is;
80 psi .060
100 psi .070
125 psi .092
160 psi .117
200 psi .150
250 psi .198
So kind of like Class 125 PVC? The stuff feels really flimsy in small sizes, but is supposed to hold together. I know I react more to crush strength than bursting strengh when I fondle items in the store. Maybe that's not the proper assessment of pipe, but I still do it.
David Thomas Overlooking Cook Inlet in Kenai, Alaska
What I am talking about is ASTM D-2239. It is NSF approved, but I have only used it for some irrigation pumping.
In the new issue of JLC there is an article on installing deep well pumps, by Rex Caudwell and that is what he recommends.
What I like about it is that you don't have any joints except at the two ends.
It is not clear from his discription, but with the sidewalk I could see that he might have to zig and zag and flexible tubing would be better than a dozen joints.