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What is DWV pipe?

Saturday, April 9, 2022

DWV stands for Drain-Waste-Vent. It is the “back half” of your plumbing pipe system that drains fluids and waste away from the house and connects to a sewer or septic system. Unlike water piping, it is not pressurized and drains by gravity using downward-sloped pipes. When installed properly by a good plumber, DWV piping resists clogging, and does not belch up sewer gas into your home or contaminate the incoming drinking water.

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Here’s some of our articles about DWV piping:

What are the code requirements for layout of drain piping under sinks? 

Why is it a problem when a trap under a sink is installed backwards? 

Why is there a flexible accordion pipe under the sink? 

How do I get rid of the sewer gas smell in my house?

What are the code requirements for plumbing vent terminations? 

What are the building code requirements for gray water reuse in Florida?

What causes a gurgling sound when a bathtub or sink drains? 

 What is the difference between a vent stack and a stack vent?

What is a "combination waste and vent" in a plumbing system? 

Why is garbage disposal not allowed at a combination waste and vent (CW&V) under a sink?

Is a washing machine drain hose required to be secured at the standpipe? 

What is the difference between water pipe and sewage (waste) pipe? 

How can I tell if a house is connected to a septic tank system or sewer?

What type of water supply and drain (DWV) pipes were commonly used in the 2000s? 

What type water supply and drain (DWV) pipes were commonly used for 1990s residential plumbing?

What type water supply and drain (DWV) pipes were commonly used for 1980s residential plumbing?

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

What type water supply and drain (DWV) pipes were commonly used for 1960s residential plumbing? 

What type water supply and drain (DWV) pipes were commonly used for 1950s residential plumbing? 

• What type of pipes were used in 1940s homes? 

• What type of pipes were used in 1930s homes?

• What type of pipes were used in 1920s homes?

Should I seal the washing machine drain hose to the standpipe?

If all the plumbing drains have water in them and you can still smell sewer gas, what's causing the problem?    

What is a "cross connection" in a home's plumbing system?

What is an "S-Trap" under my sink? Why is it a problem? 

What is a P-trap?

What is the difference between gray water and black water in the plumbing code? 

Is a sink required to have a drain stopper? 

• Can a laundry sink drain be installed without a trap under it? 

• What is a drum trap at a plumbing drain?

• Can a dishwasher drain hose be connected after the sink trap (to the trap arm)? 

How far away from the sink can I install a dishwasher? 

What is a "high drain loop" or "air gap" in a dishwasher drain hose?

• What is the minimum and maximum distance a P-trap can be below a sink? 

• Is an air admittance valve (AAV) legal by code? 

• What is a double trap in plumbing? 

• What types of plumbing traps are illegal by code? 

• How many plumbing vents through the roof are required by code?   

What is the minimum and maximum slope of the trap arm of a plumbing drain?

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