Do I need a vent? Yes.

[Greg Pizzola]

Hi All,

This is my first post on this forum so I'm hoping I'm following protocol.

I'm a DIYer looking to add some finished space to my unfinished basement. The first step of my project was installing a laundry area to a portion of the basement that will remain unfinished. I extended an existing utility sink that was tied into the main stack about 15 feet. I assumed that because there was no vent in place I wouldn't need to add one. Did I assume incorrectly? If I need a vent can I add in a studor? This sink drains my washer. I added a pic of the setup.

Appreciate in advance any advice I recieve.

Thanks,
Greg

 

[Terry]

Yes, add the Studor vent within 42" of the trap.
Venting prevents traps from siphoning, which allows sewer gas into the room. That plumbing was never right. You can't wet vent from the next floor up.

 

[Sponsor]

 

[Greg Pizzola]

Yes, add the Studor vent within 42" of the trap.
Venting prevents traps from siphoning, which allows sewer gas into the room. That plumbing was never right. You can't wet vent from the next floor up.

Thanks Terry!

 

[hj]

Technically, you need a vent that eliminates both negative and POSITIVE pressures for your installation and a Studor vent only works with negative ones.

 

[Greg Pizzola]

Technically, you need a vent that eliminates both negative and POSITIVE pressures for your installation and a Studor vent only works with negative ones.

Thanks for the response hj. What would you suggest?

 

[Standardairconditioner]

What would you suggest?

AAV's only let air into the drain.

They seal shut when pressure comes from the drain, which is the whole point of their design.

It would be silly to expect an AAV to let stinky sewage into your home.

 

[Cacher_Chick]

AAV's should only be used when there is not a viable way to run a proper vent, which is very seldom. A real vent vent which is properly installed allows air in and out, and has no mechical components to fail. An AAV must be left exposed because it will eventually fail and need to be replaced.

 

[Asktom]

Without a proper vent the positive air pressure resulting from the water falling from the floor(s) above will cause the water in the trap to slosh back and forth, some of which can run down the drain thus breaking the trap seal. This will allow sewer gas to enter the building. AAVs are cheap and easy, a real vent is not subject to mechanical failure and protects against positive pressures.