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What type water supply and drain (DWV) pipes were commonly used for 1970s residential plumbing?

Friday, July 6, 2018

The 1970s was a transitional period between metal and plastic piping. Although PVC and ABS pipe had been available for years, they became common by the end of the decade for drain (DWV) piping. Copper also overtook galvanized as the preferred water supply pipe during the ‘70s, and PVC began to be used for water service piping between the well or meter and the house, but not approved for water pipe inside homes.

Water Supply

Galvanized steel faded in popularity during the 1970s.

Copper became the “gold standard” for dependability.

PVC (white plastic) used for water service piping to house (not inside), and other exterior locations.

Drain (DWV)

Copper was used for smaller diameter (up to about 3”) DWV pipes, primarily during the first half of the decade.

Cast Iron was used for larger DWV pipes, primarily during the first half of the decade.

ABS (black plastic) pipe became more common for DWV piping in the last half of the 1970s.

PVC (white plastic) also came into common use during the latter part of the decade.

Orangeburg (bituminous fiber pipe) was used for sewer laterals up to 1973.

    Looking for the pipes used in a different decade? Click below for the one you want.
1920s  1930s 1940s 1950s  1960s   1980s  1990s 2000s  Today

    See our blog post for What do the ABS, PVC, CPVC, PB, and PEX plumbing pipe names mean? for the chemical composition behind all those acronyms. Also, you might want to read How can I tell what type of plumbing pipe I have? and What is the difference between water pipe and sewage (waste) pipe? and Are plastic pipes (PVC, CPVC, and PEX) safe for drinking water?

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Here’s links to a collection of our other blog posts about PLUMBING PIPES:

ABS Pipe

• What is the average life expectancy of ABS pipe?

What is the difference between PVC and ABS plumbing pipe?

Cast Iron Pipe 

What is the average life expectancy of cast iron pipe?

How can I tell if I have cast iron pipes in my house? 

Copper Pipe 

What is the average life expectancy of copper pipe?

• Should I use a dielectric union or brass nipple to connect copper tubing and galvanized steel pipe?

• What problems are caused by connecting copper pipe/tubing directly to galvanized steel pipe?  

CPVC Pipe 

What is the average life expectancy of CPVC pipe?

Can you connect CPVC pipe directly to a gas water heater?   

Galvanized Steel Pipe 

What is the average life expectancy of galvanized steel pipe?

Why is old galvanized steel water pipe a problem for homebuyers?

What is a galvanized nipple? 

• Should I buy a house with galvanized steel water pipes? 

Can galvanized steel pipe still be used for new water lines in a house?  

Orangeburg (bituminous fiber) Pipe 

• What is the average life expectancy of Orangeburg (bituminous fiber) pipe? 

Why is Orangeburg sewer pipe a problem and how do I know if I have it?

PEX Pipe

 What is the average life expectancy of PEX pipe? 

Can PEX pipe be installed outside?  

 Is PEX pipe freeze resistant?

PB (Polybutylene) Pipe 

What does polybutylene pipe look like? Why is it a problem? 

Does a "QEST" brand mark on pipe mean that it is polybutylene (PB)?

PVC Pipe 

• What is the average life expectancy of PVC pipe? 

Why is sunlight exposure bad for PVC pipe? 

Why can't PVC be used for water pipe inside a house? 

What is the difference between green and white sewer drain pipes? 

     Visit our PLUMBING page for other related blog posts on this subject, or go to the INDEX for a complete listing of all our articles.

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