This is one of those oddities of plumbing terminology. Seems like they should be the same thing, but they are not.

    A vent stack is a vertical pipe that is only used for venting, and runs upward from the drain piping to the open air outside the home. Vent stacks are primary vents and accept connections from other vents in a plumbing system.

    A stack vent is used for both drainage and venting. The bottom portion is a soil pipe (for drainage) and the top part is a vent. This is the kind of primary vent most often used in residential plumbing.

    Unless your are a plumber, and use these terms frequently, you may have to stop for second and think about it—like we do—before you remember which word to put first for the pipe configuration you are trying to describe.

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

• How can I protect my pipes to keep them from bursting during a hard winter freeze in North Florida?

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

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

• Why can't a sanitary tee be used for a horizontal-to-horizontal drain pipe connection? 

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

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

• What are the abandoned pipes sticking out of the wall in my house?  

• What are the code requirements for plumbing vent terminations?

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

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

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

• What is a building trap?  

• What is a dielectric union? 

• What's that powdery crust on the pipe connections at the water heater? 

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

• How can I tell what type of plumbing pipe I have?

• Why is there a flexible accordion pipe under the sink? 

• What is the difference between PVC and ABS plumbing pipe?

• What is the difference between water service pipe and water supply pipe? 

• What are the pipes on my roof? 

• How can I find out what type of water pipe runs underground from the water meter to the house (service pipe)?

• What is a P-trap?

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

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

• Which water pipes are an insurance problem and possibly uninsurable?

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

     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.