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Everyday uses for PVC water pipe

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Re: Everyday uses for PVC water pipe

#22

Post by quickthrowman »

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 are steel because it has a high melting point, it’s durable, and it’s less expensive than copper or brass. The water pressure in a fire sprinkler system can be 100-200 psi.

Re: Everyday uses for PVC water pipe

#24

Post by cameronh90 »

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…

Landscape irrigation isn't that common in a domestic setting here. We get plenty of rain normally, but in the (increasingly common) periods of drought, most people just let their lawns dry out and manually water the flowers.

Domestic fire sprinklers are also, sadly, quite uncommon. They've started to become more common in flats, particularly since Grenfell, but still, I've never had cause to touch the pipework for one. Fire safety in the UK is pretty poor compared to the USA.

Copper has has been the dominant form of indoor plumbing for ages here, so every plumber knows how to work with it. It's still seen as the preferred option, and most people, myself included, consider PEX as a cheap alternative. As far as joints go, compression fit seems to maybe be more popular now than soldering for domestic plumbers due to speed of installation, but I personally prefer soldering as I've had bad luck with compression fittings developing weeps after years. Push fit has been making some inroads - but I wouldn't trust it myself!

Re: Everyday uses for PVC water pipe

#25

Post by briHass »

genter wrote: post #12
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.

It's certainly not 'way worse'. CPVC/PVC has its advantages and disadvantages, just like every other piping method. CPVC can become less pliable over time, particularly for hot water, but properly (by code) supported/strapped and glued, it can last for decades. It, like PEX, should be run to a well-secured, copper stub out where it sticks out of the wall in an area where it could be damaged.

Copper is not without its disadvantages: it's outrageous expensive as of late, soldering can be dangerous (banned in some cases due to fire risk), it takes longer to install than most other options, and some water supplies have a composition that leads to premature failures.

PEX is a universe of options: PEX-A, PEX-B, crimp rings, clamps, plastic/brass fittings, etc. It also needs to be properly installed - PEX B has very specific locations for the crimp/clamp rings on the fitting, and the difference between a proper crimp/clamp and a failure waiting to happen is very subtle.

Re: Everyday uses for PVC water pipe

#27

Post by pengaru »

sokoloff wrote: post #18
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.

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

This has absolutely nothing to do with "pros", we're not talking about plumbing - we're talking about alternative applications for PVC. PVC hacks if you will.

The amount of time you waste trying to find fittings that match your weird ass project in the disorganized and poorly stocked shelves of the local Home Depot you probably already could have had the thing done with just some careful application of heat. You often end up with a more streamlined end result too.

Re: Everyday uses for PVC water pipe

#29

Post by function_seven »

genter wrote: post #12
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.

> This is also the reason why pvc is super dangerous for compressed air.

Back in the day all us kids knew to get the ABS stuff when building our potato cannons. I was terrified of the combustion chamber shattering right next to my face.

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