View Full Version : Has anyone used flexible pvc in residential plumbing situations?
adthern
Dec 18, 2010, 02:07 AM
I was doing some research and I was curious if there was an actual reason not to use flexible pvc in doing standard plumbing jobs? (no the "its not code" response I got at home depot).
I know its used in hot tubs and spa/pool applications. I also understand that it can be penetrated by a screw (the other reason given at HD) but so can standard PVC and copper (as the piece of pipe 5 feet long I removed with 13 screw holes in it from the subfloor).
Thanks,
Adam
massplumber2008
Dec 18, 2010, 08:14 AM
Hi Adam...
It is very rare that I agree with the home depot guys, but this time they are correct by stating that this piping material is simply NOT approved for residential plumbing systems.
I can certainly see where the stuff could come in handy, but the plumber's board that makes the rules knows that many plumbers and most consumers wouldn't hang the stuff properly and we would be getting all kinds of bellys/sags and clogged drains and vents would certainly increase in the future.
If you would like even more info. On this let me know and I'll pop it by my local Massachusetts plumbing inspector for a more "offical" answer... ;)
Mark
joypulv
Dec 18, 2010, 08:41 AM
One 'side reason' is that if you ever have to file an insurance claim you could be denied.
If you sell the house you could be sued.
If a guest gets sick from sewer gas blah blah, I realize that's getting far out there, and that these are all sort of begging the question.
People ignore code all the time and get away with it... My parents' 1967 built house is full of out of date stuff like the vent is in the chimney (a contractor friend told a story of a big explosion from such a vent) and my dad said he could care less. A subpanel was under the kitchen sink with water dripping on it. Older fluorescent lights were oozing creepy lava stuff (full of PCBs). Good luck. People call it 'temporary plumbing' like those flexible gas lines for stoves that go in and out of being code in different places.
argaiu1017
Dec 18, 2010, 10:03 PM
Hi,
As a licensed contractor in California and use UPC and CPC codes and always working on making installations as safe as possible, PVC has almost a 3.5" expansion per 100 degree Fahrenheit rise. The greatest concern is contraction in cold weather, because joints can be pulled apart. Polybutylene expands approx. twice as much as PVC.
argaiu1017
Dec 18, 2010, 10:07 PM
So anyway to answer your question about PVC in residential installation, "NO". So HD guys are correct and I am sure it is anywhere.
massplumber2008
Dec 19, 2010, 06:58 AM
Argaiu..
What does all this have to do with FLEXIBLE PVC whirlpool piping?
You said, "PVC in residential use, "NO"." Huh? Please explain.
Thank you...
Mark
Milo Dolezal
Dec 19, 2010, 10:09 AM
Mark, I think poster just gave us an example of flexible PVC use in residential applications. Some whirlpool tubs have flexible PVC piping installed between motor and jets.
argaiu1017
Dec 19, 2010, 11:54 AM
Like I said on my 1st post, pvc expands approx. 3.5" per 100degree rise. The concern is contraction in cold weather cause fittings to pull apart. It is on my 1st post.
argaiu1017
Dec 19, 2010, 12:00 PM
Whirlpool is not under constant pressure like water lines. Pvc has a service temp of 140-150degree fahrenheit.
massplumber2008
Dec 19, 2010, 01:48 PM
Hi guys:
He is asking about FLEXIBLE PVC piping... not regular schedule 40 PVC, right?
Here, an expansion rate of 3.36 inches for every 100 feet of schedule 40 PVC pipe with a temperature change of 100 F is not going to apply to flexible PVC is all.
As I said in my 1st post argaiu, flexible PVC is not approved by code... sags and hanging probably being the biggest mechanical issues I can think of.
Mark
mygirlsdad77
Dec 19, 2010, 03:47 PM
I assume the op is asking about flex pvc for drain waste and vent, not pressurized water. I believe mark is correct, with flex pvc it would be near impossible to maintain proper constant slope without saggs or bellies without supporting the entire length of pipe or at the very least having so many hangers as to be unpractical from a materials and labor perspective. In my opinion, it would also be a problem waiting to happen when it did come time to auger a plugged drain, as with some of the powerful augering machines and cutting bitts would have a very likely chance of destroying the pipe.
adthern
Dec 20, 2010, 10:48 AM
I want to thank you all for your answers, I was in fact asking only about drain. Massplumber, your answer (and the agreements) were exactly what I was asking for. I was actually only thinking of using the flexible pvc for a piece no longer than 1 foot (more to mold a fitting that I couldn't find than anything else).
I can absolutely see where it would create a potential for misuse and sags/bellies! I had not thought of that, since my idea was limited to a very small area.
I will probably post another ( foolish) question shortly ;-)
Thanks