Hello All,

I am about to piece together my first DWV waste and vent lines. The bathroom was remodeled and enlarged to accommodate a 6' tub in a new location. Since I want to keep all in check with codes for MD, I have a few questions please.
First off does any one see something terribly wrong with my current set up?
The problem I think I may encounter is the double 3" sanitary t. the water closet drains into a vent elbow which in turn is connected to the double t, from there it all goes 3 south out to the sewer. I plan on using a 1.3 - 1.6 flow toilet. I could use a 3" single t and reroute the kitchen sink to go from a 1.5 and dump into a vertical 3" which will go into a 3" wye if needed.
The picture is for demonstration. This is close to the actual waste configuration, but the pipe lengths have been shortened on the water closet. EDIT! After posting this I looked and the photo and realized that the kitchen sink is a no go since the slope will need to go the other way. Would I be OK with my wye idea and a single sanitary t below the toilet?
Thanks,
Rob
http://i488.photobucket.com/albums/rr241/robmehm/DWV.jpg

Set up sounds pretty good, only thing to watch is you slope on the horozintal pipes.

Thanks lilpoppa,

I am afraid that I have some issues with this. The problem is that I only have about 3 feet of clearance before it go's out to the sewer

Hi Moshetojinx...

I'm afraid lilpoppa missed some stuff here, so hope I caught you in time... ;)

What comes of the main stack... another bathroom or does this become the vent stack out the roof? Here, if any fixtures connect into the "main stack" fitting then you need to add an 1.5" vent to the shower/tub drain.

You CANNOT use a sanitary tee fitting on a horizontal drain pipe for a waste fittingso stick with the combination wye fitting or just a wye fitting and a 45 degree fitting for the shower/tub drain... add vent within 3 feet of the PTRAP if, as mentioned above, fixtures connect into the main stack.

You can connect a 3"x2" sanitary Tee fitting on the 3" vertical for the kitchen sink, but in my opinion, a wye fitting is always better. If you decide to pick the kitchen sink up off the horizontal drain then use a wye or wye combination fitting. Also, although 1.5" is allowed in most states for a kitchen sink, I'd run a 2" drain if possible. Install a 2" cleanout near where the sink connects to the 3" drain if it can be readily accessed and also install a 2" cleanout directly under the kitchen sink. In my area, the cleanouts are required by code, but nver mind that, if the sink ever clogs you will be super happy that they are present!

Pitch should not be an issue with only 6-7 feet of pipe as you only need 1/4" pitch per foot so you are OK there. The drain/vent pipes should be hung every 4 feet, minimum.

Finally, where is the bathroom sink drain and how are you planning to vent that? For that matter, how are you connecting all the vents and are you connecting into a vent stack or going out the roof?

Answer my questions and let me know more here, OK?

Mark

Good Morning Mark,
First thank you for your thorough answer. The "main stack" only has the bathroom sink going into it and then it vent straight up through the roof at that point. I only have one bathroom on the main floor (cape cod), and may tie into the 3" vertical stack for a 2nd floor bathroom in the future. Per your and others suggestions, I am switching over to wyes on the horizontal and the kitchen sink will take another route. The venting seem to be the easiest of all of this. The bathroom sink is not vented since it is 24" from the 3" main and connects via a 3x1.5x3 sanitary t. The shower is 6 feet from the 3" main vent and has it's own 2" vent which connects to the 3" main in the attic.

Thanks,
Rob

Glad to help!

If you plan to add a bathroom into the 3" main stack in the future then you cannot add the sink into the main stack without adding an additional vent to the sink.

The toilet vent must stay 2" all the way until it connects into a 2" or larger vent.

More questions? Let me know, OK?

I'll pop back in around lunch time or so...

Mark