installing cpvc tubing

Old 08-23-02, 07:35 AM
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Post installing cpvc tubing

I want to build my rough-in shower with cpvc pipe. Is this a good idea or will it not hold up to the pressure or years of service?
Old 08-23-02, 09:26 PM
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installing cpvc tubing


First question is why do you want to use it?
Second, is do you have copper pipes or galvanized now?

CPVC tubing and fittings are perfect for areas of the country that have aggressive water that eats away at copper pipes. This aggressive water can sometimes eat through copper pipe within eight years. CPVC is unaffected by aggressive water, and its smooth inner surface won't collect mineral deposits. It's also less expensive than copper.

This system is designed to be very user-friendly, and because the outside diameter of CPVC tubing is sized the same as copper pipe, the grip-style mechanical fittings can be used on both copper and CPVC.

Don't confuse CPVC with the plastic polybutylene systems that were a problem more than a decade ago. Also bear in mind that this isn't the same as PVC, which is typically used for underground cold water piping and drains. You can quickly distinguish between the light beige color of CPVC and the bright white of PVC. If you're not sure, look for the printing on the side of the pipe. CPVC tubing is available at home centers and hardware stores in 1/2-in. and 3/4-in. diameters in 10-ft. lengths.

Are there any drawbacks to CPVC?

You may have heard claims about CPVC and chemical leaching, the transfer of chemicals from the pipe into the water. Studies have proved that CPVC tubing and fittings are completely safe for home water supplies. In fact, CPVC has been successfully used in homes for more than 35 years.

Be aware that many home copper or steel water pipe systems are used as grounding for electrical wiring. CPVC is not a good conductor, so changing to it may change your grounding system. Check with an electrician if you think you've broken the continuity of your electrical grounding.

CPVC is not as tough as copper or galvanized steel. Take care not to strike it with a hammer, and be sure to use steel nail plates in wall framing if a nail or screw puncture is a possibility. Because of its flexibility (which can be an asset), you'll need to support it more often than copper or galvanized steel--every 32 to 36 in.

CPVC is code compliant--almost everywhere

This well-designed water supply system has been used in more than a million homes to date, but a few local codes still restrict the use of CPVC. CPVC is capable of carrying 180-degree water at 100 psi (water in the average home is about 125 degrees at 50 psi). Contact your local plumbing inspector to see if CPVC is permitted in your area.

If I had copper now, I would maintain using the same. If you have galvanized now, I would consider changing your plumbing system. Are you experiencing lower water pressure lately? Plastic piping in general has not been approved in all municipalities and thus that is why plumbers are reluctant to use plastic. Most plumbing in years past has been galvanize or copper and thus when repairs are required, most plumbers have the parts to repair within their vehicles.

Hope this helps!
Old 08-24-02, 06:04 AM
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Doug said it all about CPVC.
Here is an illustrated CPVC piping how-to article from Reader's Digest "The Family Handyman" magazine that also may help you:
Good Luck!
Old 08-31-02, 09:56 PM
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one drawback. you have to wait for the glue to set before you can test for leaks. takes 24 hours to set up by the book. I like copper where you can test it 5 minutes after you solder. Matter of patience. Other than that its great stuff. More flexible for fitting in walls with less joints.

Hope this helps-Josh
Old 09-04-02, 12:42 PM
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Copper-to-CPVC connection

Does anyone have any knowledge of the reliability of those mechanical transition connectors? If they have a rubber washer in them, won't they be prone to failure as the rubber degrades? I'd want to be sure they'll last before I seal them up in the wall.
Old 09-04-02, 07:20 PM
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From what I know of the connectors, I have not heard of any problems with mechanical fittings, but the problems have been associated with cracked pipes, fittings coming apart - basically "SOMEONE WASN'T CAREFULL AND THOROUGH!"

I attached a link to a site that explains more about things;

Another think I came upon was this article and it goes through benefits and considerations of using CPVC. Just thought you might want to read it.

Benefits of CPVC pipe include:

Resistance to corrosion and abrasion
Smooth bore for improved flow and reduces water noise
High impact strength
Easy, cost-effective installation
Competitively priced vs. copper
Lightweight reduces heavy lifting
Less subject to jobsite theft
Self-insulating to minimize thermal loss
Integral flame retardancy and low smoke density
Pressure rating of 100 PSI @ 180° F, 400 PSI at 73° F
Short-term pressure rating > 200 PSI
Flexibility virtually eliminates water hammer (no water hammer arrestors required under normal conditions)
Inert to acidic soils and corrosive water supplies
Can be buried directly under slabs with no chemical interaction with concrete
Eliminates pressure leaks at solder joints
Easy for DIY'ers
Virtually no sweating or condensation
Relative price stability over time
Can be pressure tested in 10 minutes

Considerations of CPVC pipe include:

Generally limited to 1/2" to 2" Copper Pipe Size
Some complaints of "plastic taste" in water
Fittings and pipe subject to cracking or damage on job site if dropped or stepped on
Solvents used to join fittings and pipe contain volatile organic compounds (VOCs) which are known pollutants and require proper ventilation during installation
Subject to melting during a fire (becomes viscous at 395° F)
High coefficient of expansivity (1 inch in 50 feet over 50-degree temperature change) (3.4x10-5 in/in/°F)
Inner CPVC pipe surface can support the growth of bacteria including legionellae pneumophilia (ref. A Comparison of the Colonization by Bacteria of Copper and Other Materials Commonly Used in Plumbing Systems with Special Reference to Legionella Pneumophila)
Due to ease of installation, CPVC is sometimes installed by less skilled labor, potentially resulting in more frequent incidence of improper workmanship.
Subject to cracking during earthquakes
Generally requires a 24-hour cure period before pressurizing with water

Standards and code compliance (eg. FlowGuard GoldŽ)

Meets or exceeds ANSI/NSF Standard 61 for potable water
Meets of exceeds all ASTM and industry standards
Meets model building codes, BOCA National Plumbing Code, National Standard Plumbing Code, Standard Plumbing Code, Uniform Plumbing Code, CABO 1- and 2-Family Dwelling Code, Canadian Plumbing Code

Either CPVC or copper plumbing can make a suitable infrastructure for reliable delivery of potable water. CPVC is best in situations where aggressive or acidic water is prevalent (pH less than 7) and there is no acid neutralization scheme in place. CPVC has been in use for over 35 years and provides reliable service assuming proper installation is observed. Although most model building codes now approve use of CPVC, always check with your local building department to ensure its compliance in your area. Some cities or states have specific restrictions on the use of CPVC. Copper plumbing is still king when it comes to market share and consumer preference. To avoid pin hole leaks and copper toxicity, copper pipe works best in neutral to slightly basic water conditions (pH 7.0 - 8.5). If installed correctly, along with attention to mitigation of water hammer and erosion due to aggressive water or soil, copper plumbing can last the life of the structure with little maintenance and overall long-term lifecycle savings

Hope this all helps!
Old 09-04-02, 08:43 PM
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the only problems ive had with cpvc plumbing are

1 gate type shut off valves. Throw these away. They couldnt be any worse. For the extra dollar per valve buy a ball valve. First off its full flow so less restriction. second off it cant be installed "backwards" third it actually works! gate types seem to leak a "lil bit" even fully shut off. Just the nature of the cheaper valve.

2 cpvc to metal connections are prone to leaking. This is possibly a result of misuse of fittings. They make screwed male end fittings but these are to be used ONLY with cold lines not hot. I use a female receiver with an integral neoprene washer to receive a short galv pipe nipple and then go from there with metal shut offs for toilet supply and sink and copper 3/8 compression lines. This is very reliable and virtually leak proof in my mind. Have had very good results with this. Used it for a sink/toilet/hot water heater. All of which are leak free over 1 year later.

HOpe this helps-Josh

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