View Full Version : New Laundry Vent

07-11-2010, 10:41 AM
I have gutted a bathroom and I am currently in the process of converting it into a laundry room. The space is 13x6.5 and things are coming along nicely. I removed the linoleum sub floor and particle board below it as well as a 400 pound cast iron tub. The drain material is ABS so it is pretty easy to work with even for me. I have already removed the closet flange from the main stack and glued everything in place.

I would like to remove the bathtub drain pipe and run a new 2" ABS drain in the wall and connect it to the existing drain pipe below the floor (I have access to it). It appears the bathtub vented off the vent which is right next to the sink (which will become a laundry sink). Everything is open including the ceiling and walls and the only thing above me is a flat tar and gravel roof. I planned on running a new 2" vent through roof and connecting the laundry drain to it. This will keep everything in one stud bay and keep me from drilling through three studs to connect to the current drain. Any objections to this?

I was going to use a 2 1/4" hole saw to make the cuts for the new pipe. The wood is from the 1920's so it is probably as dry as it is going to get. Is 2 1/4" enough or should I go bigger?

Finally, does anyone have any objections to using the "Gator bite" "Shark bite" or other solder-less plumbing connections?

07-11-2010, 03:56 PM
It's tough to get the p-trap in the same bay, most of the time we drill at least one.
You can run the vent separate, or revent at 42"

If you are using copper, I would buy a torch and solder them.
We use sharkbites on rare occasion, but normally just one or two. Beyond that you should really solder it up, or use PEX.


07-12-2010, 08:11 AM
Thanks Terry. Can I run the vent through the ceiling and connect it to the waste pipe below the floor and just have the washer trap on it? I am not asking this correctly but basically I am asking if I have to connect the horizontal vent in the photo you posted?

07-12-2010, 09:13 AM
You can run the vent separate, or revent at 42"

Either way.

07-12-2010, 09:17 AM
uote; Can I run the vent through the ceiling and connect it to the waste pipe below the floor and just have the washer trap on it?

There is no way we can tell what you intend to do by reading that statement. Reading it one way the answer would be yes, but in another interpretation, then, no.

07-12-2010, 08:56 PM
Hopefully this helps explain my question.

07-13-2010, 07:23 AM
2 1/4" is too small for 2" pipe.

Just a side note: many folks would consider removing a bathroom from a house sacrilige. The number of bathrooms seems to be a big deal in the selling price of a house!

07-13-2010, 02:22 PM
I realize that removing a bathroom is risky but there are four bathrooms in the house (three on the main level and one downstairs) but the laundry is in the unfinished dundgeon. Removing the bathroom makes the house a 4 bed 3 bath with a bath directly across the hall from two of the rooms and the other 2 are suited.

What size hole saw should I use to drill the hole in the sole plate? Also, I plan to tie into the drain which can be seen through the floor joists in the photo. The drain is 2" ABS. I have pleanty of room to maintain the slope of the pipe but when I tie into the drain do I have to come in through the top? I have read the wye has to be greater than 45 degrees in relation to the drain pipe, is this accurate? Thanks for your help

07-14-2010, 01:40 PM
The correct size hole saw is 2 9/16" for 2" abs pipe yes your picture looks good