So I added in my sink, and it works great.

Now I am trying to reconfigure my ABS standpipe and ptrap that my washing machine uses.

I need to cut off and redo it and add a AAV. So what's the best way to attach PVC to an old ABS piping? Is there any type of glue or hybrid adapter I could use? It seems like a typical rubber coupling just doesn't seem sturdy enough, especially if its on a horizontal run.



BTW, I didn't realize how important an AAV is. I was wondering why it would smell down there after someone would take a shower. As it turns out the shower water was sucking out the water in the washing machine ptrap.

Hi Doza:

Technically speaking you cannot join ABS to PVC directly...

Here, I would recommend an ALL-PURPOSE CEMENT (see picture... available at all home improvement stores) and I would have you cement a PVC female adapter onto the PVC pipe and an ABS male adapter onto the ABS pipe. Let them dry and then use some pipe dope or teflon tape on the male fitting and scew the two adapters together. From there add sanitary tee fitting, AAV and p-trap, etc.

This will make a strong connection... especially on the horizontal.

Be sure to pitch pipe at 1/4" per foot of pipe and also be sure to have a standpipe coming out of the ptrap at about 30" tall.

Let us know if need more info.

MARK