DIY Home Improvement Forum banner

existing venting ok for new toilet, sink, and washing machine?

2K views 2 replies 2 participants last post by  dingeman 
#1 · (Edited)
I'm turning a home office room into a laundry room and 1/2 bathroom. I want to install a toilet with a 3 " waste line, tie a 2" waste line from the sink into the 3" waste line, and also tie the 2" waste line from the washing machine into the 3" toilet waste line. I would then run the 3" new toilet waste line about 20 feet or so where it would tie into an existing 3" toilet waste line that has venting through the main toilet stack and through the roof of my house. I cannot access any existing roof plumbing vents where this new bathroom is being installed. Can I rely/use the existing toilet stack venting for these new fixtures, or do the new fixtures need their own, new venting? If I had to install new venting, it would go through the outside wall then go vertical with a new, exposed ABS vent pipe up over the side edge of the roof and look rather ugly.

My house is near Tacoma, Washington, and was built in 1935. The existing office is on the main floor adjacent to an outside wall. I have access to install all of the waste pipe via the basement, but I cannot get to any existing plumbing vents due to their location near the center of the house and behind many walls. The ceiling of the office room is the floor of a bedroom above it, so I cannot access that space either.

I would prefer not to use an air admittance valve(s) for the reasons others on this forum have previously mentioned. So, my options are to rely on the existing vents on the main waste stack, or to install the ugly new vent pipe to the outside of the house. Any thoughts? Thanks for your help!

Here's a crude diagram of what I propose:
 

Attachments

See less See more
#2 ·
Every fixture needs a vent within certain distances to their traps. You far exceed this. Example per UPC - 2" trap (washing machine) max. length is 5ft
Lav would be 3'-6" and a WC is 6ft. So 20' is out of the question. Plus, you are trying to horz. wet vent which I think is not legal in Tacoma.
You need to vent those fixtures thru the roof or tie into an existing 3 or 4" vent above them. Around my parts, vents on ext side walls are not allowed.
Can you run the vent up through the bedroom closet(enclose in a chase)?
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top