The Advantages and Disadvantages of Different Residential Plumbing Materials

Updated on July 9, 2013
Source

Over the years, the art and science of plumbing has changed dramatically. From the first Terra Cotta pipes in about 1700 B.C. to the newest PEX pipe technology today, no building is complete without plumbing. If it weren't for plumbing and plumbing professionals, the urban sprawl that we have experienced today would not have been possible. And if it weren't for pipes, plumbing would not be possible either. In this article I will discuss and compare the advantages and disadvantages of many of the pipe technologies that have existed or currently exist on the market for residential use.

Cast Iron Pipe
Cast Iron Pipe | Source

Cast Iron Pipe

In the 1960s cast iron pipes were the most popular form of plumbing in residential construction. This pipe was cheap and relatively easy to install for its time. It was also noted for its strength and ability to withstand high pressures. At the time, this made it ideal for home installation. Unfortunately for cast iron, it had one major flaw. This pipe was prone to failure due to rusting. Most cast iron plumbing systems had at least one leak within 20 years of installation, but many homes had more than their fair share of plumbing problems. Cast iron pipes were also known to leave a metallic taste the water. This was due to the iron leaching into the water from the rusting of the pipe. Today, cast iron pipe is no longer used for residential plumbing because of its faults.

Copper Pipes
Copper Pipes | Source

Copper Pipe

Copper is probably the most commonly used plumbing materials in the United States today. This plumbing material offers long term durability and stability yet is soft enough to resist shattering upon impact. Its so durable in fact that copper pipes can even be used outdoors in both above and underground setting. Another advantage to copper plumbing is its natural ability to resist the growth of bacteria. This is important because it helps to ensure that your water supply is clean and safe to use. And finally, copper has a very high melting point and is able to resist deformation. This means that during a house fire, the plumbing may remain intact and could possibly be reused.

Despite all the great things that copper has to offer, there are a few disadvantages. The first notable disadvantage is the fact the copper is expensive to purchase and install. Installation of this plumbing requires soldering equipment and the skills of a trained plumber. Copper pipes can also be subjected to major corrosion if the water it contains becomes too acidic. In addition to this, copper pipes can leave water with a slightly metallic taste.

A Stack of PVC Pipe
A Stack of PVC Pipe | Source

PVC Pipe

Next to copper, PVC pipe is also one of the most common materials used for residential plumbing applications. PVC is great because it is an inert and stable material that resists corrosion. It is also a very cheap material that is quick and easy to install. A minimal amount of skills and tools are required to properly install PVC pipes in a home.

The main disadvantages to PVC pipe is that it is very brittle that can break or crack if miss-handled. This is especially true for properties located in cold climates. In addition to this, it can only be used indoors and is not intended for hot water distribution (it has a maximum service temperature of 140 degrees Fahrenheit). Because of this, care must be taken when installed near hot items such as furnaces or ovens.

CPVC Pipe

CPVC stands for Chlorinated Polyvinyl Chloride. This yellowish plastic polymer was invented to handle the higher temperatures that regular PVC could not. It also is slightly stronger than standard PVC. CPVC has a few advantages over copper as well. It is generally a stable compound and will not corrode as easily as copper pipes can. CPVC also requires about 25% less time to install than copper does (though it does require more bracing). However, it is not as easy to install as other plumbing materials such as PEX.

The disadvantages of CPVC include that it is brittle and it can't withstand very high temperatures like copper can. Another disadvantage to CPVC is it's high thermal expansion coefficient. Because of this, CPVC may not be the best choice for climates that experience wide variations in temperature. Additionally, CPVC typically costs about twice as much as standard PVC does.

Red Color Coded PEX Pipe
Red Color Coded PEX Pipe | Source

PEX Pipe

PEX is shorthand for "Cross-Linked polyethylene." This material is relatively new to the field of plumbing (only appearing in the USA about 20 years ago) and offers some clear advantages over other available materials. The first, and most notable, characteristic about this material is that it is flexible. The flexibility of the pipe allows installers to avoid many obstacles while also using less fittings. The speed of installation is also increased by the fact that the pipe fittings are generally of the compression type. And finally, PEX is very good at resisting the effects of freeze and thaw because of its flexibility.

However, there are some disadvantages to this material. Installation generally requires the use of extensive bracing and supports. If not done properly, the pipes can move within the walls when the water is turned on and off (water hammer). PEX cannot be used outdoors unless it has a UV blocking coating. PEX is also a softer material that rodents seem to enjoy chewing on. This can lead to a sudden and catastrophic loss of water pressure (and potential water damage) within a home.

Summary

The overall consensus is this: Plastic pipes are the cheapest to purchase and install, however they generally cannot be used outdoors and have relatively low service temperatures. Copper is the way to go if you need to deliver hot water or want something that this durable and long lasting. Today, many houses are being constructed using a combination of PEX and copper plumbing. This combines the ease of installation of PEX with the durability and strength of copper. This affords new homeowners the best combination of advantages that the residential plumbing industry has to offer.

Below is a table which summarizes the key characteristics and information for the various types of plumbing materials for comparison purposes.

Comparison of Properties for Common Pipe Materials

 
Cast Iron
Copper (Type M) *
CPVC (Schedule 40)
PVC (Schedule 40)
PEX (Class A)
Cost
N/A
$3.90/ft
$0.83/ft
$0.20/ft
$0.46/ft
Pressure Rating @ 73°F
200 psi
225 psi
400 psi
100 psi
150 psi
Pressure Rating @ 180°F
200 psi
120 psi
100 psi
N/A
100 psi
Max Service Temp
200 °F
200 °F
200 °F
140°F
200 °F
Softening Point (Vicat Test)
N/A
N/A
295 °F
250 °F
255 °F
Melting Point
2,300 °F
1,981 °F
428 °F
360 °F
270 °F
Thermal Expansion
0.000006 in/in/°F
0.000009 in/in/°F
0.000037 in/in/°F
0.000028 in/in/°F
0.000083 in/in/°F
Tensile Strength @ 180°F
25,000 lbs
34,800 lbs
8,700 lbs
6,500 lbs
1,806 lbs
Weight
12.2 lbs/ft
0.33 lbs/ft
0.23 lbs/ft
0.21 lbs/ft
0.1 lbs/ft
Specific Gravity
7.89
8.96
1.54
1.4
0.94
Corrosion Resitance
Low
Medium
High
High
High
Life Expectancy
20-75 years
50-75 years
75-100 years
75-100 years
75-100 years
Flexibility
None
Slight
Slight
Slight
High
Thermal Conductivity
3.8 Btu in /h ft² °F
19.2 Btu in /h ft² °F
1 Btu in /h ft² °F
1.1 Btu in /h ft² °F
3.2 Btu in /h ft² °F
Specific Heat
0.11 Btu/lb °F
0.09 Btu/lb °F
0.2 Btu/lb °F
0.25 Btu/lb °F
0.55 Btu/lb °F

The data for this table was compiled from more than 100 resources including textbooks, websites, and other technical guides.

Properties given are for 3/4" or equivalent pipe except for Cast Iron which has a diameter of 3 inches.

*Joining Method and material will govern the pressure rating for copper. In this table, a 50-50 tin/lead solder is used because it is the weakest of all the common copper joining methods.

Questions & Answers

    Comments

      0 of 8192 characters used
      Post Comment

      • Cajun Maintenance profile image

        Kevin Hussey 

        3 years ago from Baton Rouge LA

        We had cast iron as a drain line in our kitchen and it failed. We had to jackhammer our floor and replace it with PVC. Insurance covered this. Downside is that they would only pay to repair the section that failed.... there is probably another 50ft (or more) of the cast iron in the slab that will fail at some point in the future.

      • profile image

        Johng36 

        3 years ago

        Good website! I truly love how it is easy on my eyes and the data are well written. I'm wondering how I could be notified whenever a new post has been made. I have subscribed to your RSS feed which must do the trick! Have a great day! bdkaacdadffb

      • CWanamaker profile imageAUTHOR

        CWanamaker 

        3 years ago from Arizona

        Lead is interesting as it was used in some of the earliest forms of plumbing. In fact, the word "plumbing" comes from the Latin word for Lead. I didn't include this material in the list because it it is rarely used today, if it all, due to the possibility of lead poisoning.

      • profile image

        steven 

        3 years ago

        what about lead pipe ?

      • raizhel profile image

        Ruby S. 

        4 years ago

        Very useful information particularly for people that are looking for different types of pipes. This will educate them what pipe should they choose.

      working

      This website uses cookies

      As a user in the EEA, your approval is needed on a few things. To provide a better website experience, dengarden.com uses cookies (and other similar technologies) and may collect, process, and share personal data. Please choose which areas of our service you consent to our doing so.

      For more information on managing or withdrawing consents and how we handle data, visit our Privacy Policy at: https://dengarden.com/privacy-policy#gdpr

      Show Details
      Necessary
      HubPages Device IDThis is used to identify particular browsers or devices when the access the service, and is used for security reasons.
      LoginThis is necessary to sign in to the HubPages Service.
      Google RecaptchaThis is used to prevent bots and spam. (Privacy Policy)
      AkismetThis is used to detect comment spam. (Privacy Policy)
      HubPages Google AnalyticsThis is used to provide data on traffic to our website, all personally identifyable data is anonymized. (Privacy Policy)
      HubPages Traffic PixelThis is used to collect data on traffic to articles and other pages on our site. Unless you are signed in to a HubPages account, all personally identifiable information is anonymized.
      Amazon Web ServicesThis is a cloud services platform that we used to host our service. (Privacy Policy)
      CloudflareThis is a cloud CDN service that we use to efficiently deliver files required for our service to operate such as javascript, cascading style sheets, images, and videos. (Privacy Policy)
      Google Hosted LibrariesJavascript software libraries such as jQuery are loaded at endpoints on the googleapis.com or gstatic.com domains, for performance and efficiency reasons. (Privacy Policy)
      Features
      Google Custom SearchThis is feature allows you to search the site. (Privacy Policy)
      Google MapsSome articles have Google Maps embedded in them. (Privacy Policy)
      Google ChartsThis is used to display charts and graphs on articles and the author center. (Privacy Policy)
      Google AdSense Host APIThis service allows you to sign up for or associate a Google AdSense account with HubPages, so that you can earn money from ads on your articles. No data is shared unless you engage with this feature. (Privacy Policy)
      Google YouTubeSome articles have YouTube videos embedded in them. (Privacy Policy)
      VimeoSome articles have Vimeo videos embedded in them. (Privacy Policy)
      PaypalThis is used for a registered author who enrolls in the HubPages Earnings program and requests to be paid via PayPal. No data is shared with Paypal unless you engage with this feature. (Privacy Policy)
      Facebook LoginYou can use this to streamline signing up for, or signing in to your Hubpages account. No data is shared with Facebook unless you engage with this feature. (Privacy Policy)
      MavenThis supports the Maven widget and search functionality. (Privacy Policy)
      Marketing
      Google AdSenseThis is an ad network. (Privacy Policy)
      Google DoubleClickGoogle provides ad serving technology and runs an ad network. (Privacy Policy)
      Index ExchangeThis is an ad network. (Privacy Policy)
      SovrnThis is an ad network. (Privacy Policy)
      Facebook AdsThis is an ad network. (Privacy Policy)
      Amazon Unified Ad MarketplaceThis is an ad network. (Privacy Policy)
      AppNexusThis is an ad network. (Privacy Policy)
      OpenxThis is an ad network. (Privacy Policy)
      Rubicon ProjectThis is an ad network. (Privacy Policy)
      TripleLiftThis is an ad network. (Privacy Policy)
      Say MediaWe partner with Say Media to deliver ad campaigns on our sites. (Privacy Policy)
      Remarketing PixelsWe may use remarketing pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to advertise the HubPages Service to people that have visited our sites.
      Conversion Tracking PixelsWe may use conversion tracking pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to identify when an advertisement has successfully resulted in the desired action, such as signing up for the HubPages Service or publishing an article on the HubPages Service.
      Statistics
      Author Google AnalyticsThis is used to provide traffic data and reports to the authors of articles on the HubPages Service. (Privacy Policy)
      ComscoreComScore is a media measurement and analytics company providing marketing data and analytics to enterprises, media and advertising agencies, and publishers. Non-consent will result in ComScore only processing obfuscated personal data. (Privacy Policy)
      Amazon Tracking PixelSome articles display amazon products as part of the Amazon Affiliate program, this pixel provides traffic statistics for those products (Privacy Policy)