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Everyday uses for PVC water pipe

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Re: Everyday uses for PVC water pipe

#11

Post by cameronh90 »

amluto wrote: post #9

Interestingly, plumbing your house with PVC water pipe is not a fantastic idea and is not allowed under most plumbing codes. The specific issue is that PVC loses strength at higher temperatures, so performance at household water pressures with household hot water is somewhat marginal. Manufacturers don’t rate their pipe at all above 140 degrees F. Having your pipe burst when you run hot water through it is undesirabl…

I don't think I've ever seen PVC/CPVC pipe used for water in the UK, only ever seen it used for electrical conduits.

Most indoor water pipes are still copper but PEX is becoming more popular. Outdoor is now nearly always MDPE.

Re: Everyday uses for PVC water pipe

#12

Post by genter »

amluto wrote: post #9

Interestingly, plumbing your house with PVC water pipe is not a fantastic idea and is not allowed under most plumbing codes. The specific issue is that PVC loses strength at higher temperatures, so performance at household water pressures with household hot water is somewhat marginal. Manufacturers don’t rate their pipe at all above 140 degrees F. Having your pipe burst when you run hot water through it is undesirabl…

CPVC might be better than PVC, but it's still way worse than copper or pex. Both PVC and CPVC will shatter if stressed beyond it's yield strength. Go hit it with a hammer, and compare that to hitting a copper pipe or pex. This is also the reason why pvc is super dangerous for compressed air.

Re: Everyday uses for PVC water pipe

#13

Post by seabrookmx »

amluto wrote: post #9

Interestingly, plumbing your house with PVC water pipe is not a fantastic idea and is not allowed under most plumbing codes. The specific issue is that PVC loses strength at higher temperatures, so performance at household water pressures with household hot water is somewhat marginal. Manufacturers don’t rate their pipe at all above 140 degrees F. Having your pipe burst when you run hot water through it is undesirabl…

In my experience 99% of indoor plumbing in new builds in Canada (US too I believe) is PEX, not (C)PVC.

PVC is common in sewage, drainage, and as conduit.

Re: Everyday uses for PVC water pipe

#14

Post by amluto »

cameronh90 wrote: post #11
amluto wrote: post #9

Interestingly, plumbing your house with PVC water pipe is not a fantastic idea and is not allowed under most plumbing codes. The specific issue is that PVC loses strength at higher temperatures, so performance at household water pressures with household hot water is somewhat marginal. Manufacturers don’t rate their pipe at all above 140 degrees F. Having your pipe burst when you run hot water through it is undesirabl…

I don't think I've ever seen PVC/CPVC pipe used for water in the UK, only ever seen it used for electrical conduits. Most indoor water pipes are still copper but PEX is becoming more popular. Outdoor is now nearly always MDPE.

Huh. In the US, HDPE outdoors is somewhat common in larger installations and for utilities, and PVC is used for almost all landscape irrigation. Galvanized steel is still surprisingly common indoors and outdoors despite its near complete lack of redeeming features.

Indoors, fancy contractors seem to prefer copper and less fancy contractors seem to prefer PEX. Those fancy copper-using contractors seem to mostly mess up and use non-water-soluble flux, which is against code and is very much a mistake on cold water pipes.

Residential fire sprinkler pipes are almost always CPVC. PEX is permitted in most jurisdictions if the pressure is regulated, but almost no one uses it despite being much less fiddly than CPVC. (Commercial fire sprinkler pipes seem to be mostly steel (!). I don’t know why. It always seems like a dubious idea to me.)

Re: Everyday uses for PVC water pipe

#16

Post by sokoloff »

amluto wrote: post #14
cameronh90 wrote: post #11

Earlier quoted context omitted.

I don't think I've ever seen PVC/CPVC pipe used for water in the UK, only ever seen it used for electrical conduits. Most indoor water pipes are still copper but PEX is becoming more popular. Outdoor is now nearly always MDPE.

Huh. In the US, HDPE outdoors is somewhat common in larger installations and for utilities, and PVC is used for almost all landscape irrigation. Galvanized steel is still surprisingly common indoors and outdoors despite its near complete lack of redeeming features. Indoors, fancy contractors seem to prefer copper and less fancy contractors seem to prefer PEX. Those fancy copper-using contractors seem to mostly mess u…

Irrigation is PVC in parts of the US, but black poly in others. I’m in New England where black poly is much more common (as it’s somewhat more freeze breakage resistant, even though we still blow them out). PVC is more common in areas with mild winters.

Re: Everyday uses for PVC water pipe

#17

Post by amluto »

seabrookmx wrote: post #13
amluto wrote: post #9

Interestingly, plumbing your house with PVC water pipe is not a fantastic idea and is not allowed under most plumbing codes. The specific issue is that PVC loses strength at higher temperatures, so performance at household water pressures with household hot water is somewhat marginal. Manufacturers don’t rate their pipe at all above 140 degrees F. Having your pipe burst when you run hot water through it is undesirabl…

In my experience 99% of indoor plumbing in new builds in Canada (US too I believe) is PEX, not (C)PVC. PVC is common in sewage, drainage, and as conduit.

PVC is quite common for water utility use in the US in the form of AWWA C900. I once said hi to the project engineer of a water main replacement project (he was walking around the site), and he waxed poetic about C900 pipe. It’s installed using crowbars, and the joints need to be externally restrained.

Those dinky 1” pipes in your house develop quite modest tension at 100psi. 8” underground pipes are a whole different story.

Re: Everyday uses for PVC water pipe

#18

Post by sokoloff »

pengaru wrote: post #7

To not highlight the power of heating PVC pipe to conform into any shape you want is to kind of miss half the PVC story. You can do without unions altogether by just heating one end enough to flare it, then slide the other pipe into the flare while heating more to let it conform and produce a union lap joint in-situ. Mastering heating is key to avoiding wasting money on tons of adapters which rarely even produce exac…

At $1-2/minute of labor, there’s a reason pros use the fittings.

Re: Everyday uses for PVC water pipe

#19

Post by elihu »

Making cool stuff out of cheap materials is great, but as I understand it, PVC itself is nasty stuff (even compared with other plastics) that we should probably be avoiding if we can.

I'm not sure what would work as a good general-purpose replacement for PVC for making things out of though. I'm not sure if ABS is available in the narrow diameters that PVC is. Pex is more bendy. Bamboo is strong, but not uniform. Wooden dowels or aluminum tube could work for some things, but it'd be more expensive.

Re: Everyday uses for PVC water pipe

#20

Post by dessimus »

amluto wrote: post #14
cameronh90 wrote: post #11

Earlier quoted context omitted.

I don't think I've ever seen PVC/CPVC pipe used for water in the UK, only ever seen it used for electrical conduits. Most indoor water pipes are still copper but PEX is becoming more popular. Outdoor is now nearly always MDPE.

Huh. In the US, HDPE outdoors is somewhat common in larger installations and for utilities, and PVC is used for almost all landscape irrigation. Galvanized steel is still surprisingly common indoors and outdoors despite its near complete lack of redeeming features. Indoors, fancy contractors seem to prefer copper and less fancy contractors seem to prefer PEX. Those fancy copper-using contractors seem to mostly mess u…

> (Commercial fire sprinkler pipes seem to be mostly steel (!). I don’t know why. It always seems like a dubious idea to me.)

Because steel can withstand much higher temperatures than CPVC, PVC, or Pex, by at least an order of magnitude, not to mention withstand much higher water pressure too.

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