My first post

**Willie Two** · 01-14-2011, 08:29 AM

Firstly I'd like to thank all the experts here who are willing to help the DYSers. I am in a different trade, more commercial, but I also like to help other people do things the right way if I can. Thanks again. I am building a new home myself from the ground up. Currently just in the planning stages, I will be putting in two main floor bathrooms with almost back to back water closets common to the water wall. There will be about 4 feet between the centers of the toilet flanges. I want to place the stack in the best location and I have my first of many questions ( I'll post more questions later )

The question is can I enter the vertical 3 inch pipe with what would be like a double "Y" fitting or should I put one entry just below the other. The stack will be straight up vented and the area underneath the floor joists is a 4 foot crawl space. After the toilets are connect the 3 or what could be 4 inch drain pipe will travel in a sloped / horizontal run about 30 feet to exit the crawlspace into the main drain. Hope this question makes sense. I am in Canada. Thanks to all who reply.

**Willie Two** · 01-14-2011, 05:10 PM

Anybody ??

hj · 01-15-2011, 06:04 AM

neither a ]"double Y", nor a sanitary cross, is the correct fitting. You want a "back to back fixture fitting", which halfway between a sanitary cross and a double combination Y-1/8 bend. For two toilets, all you need is a 3" drain line. There are many good locations for the vertical line between the toilets, the BEST one will depend on HOW the toilets line up with the floor framing.

**Willie Two** · 01-15-2011, 08:55 AM

Thanks for your reply, the good thing here is the floor joists are not framed yet, easy to reposition the joists or do a "hatch frame" as required to get a well planned out drain system. I went to the canplas website but could not find the fitting you speak of, can you post a picture ?? The entire system will consist of 2 tubs, almost back to back and 2 sinks back to back. I will post a picture as soon as I figure out how

Thanks again.

**Basement_Lurker** · 01-15-2011, 10:50 AM

canplas does make a double fixture fitting (abs), but you will have to look hard for the #. Don't expect the guys at the counter to know what you are talking about, and certainly not the big box helper. It will also cost you around 50 bux or so for the one fitting.

**Willie Two** · 01-15-2011, 03:36 PM

Under the floor is just a crawlspace, never to developed. For me this is just about doing it correctly, it will be inspected, and having it work well. I've attached pictures for you experts to pick apart , please do.

**Basement_Lurker** · 01-16-2011, 01:16 AM

on paper that looks fairly reasonable, however your lower toilet connection is at risk from the upper one, and you should run at least 2" to both of your double fixture tees.

**Willie Two** · 01-16-2011, 08:16 AM

I have lots of room and don't mind buying extra pipe

. With all the fancy toilets out there I don't want any "flushing" problems after the house is built. That being said, is this revised arrangement better ?? Thanks BTW the trap arms should read 1 1/2 not 1/2 as shown.

hj · 01-16-2011, 11:56 AM

Yes, but you still cannot use a "double fixture tee" for the sinks, either. This is what it looks like and it does NOT cost 50 bucks, regardless of its size.

**Willie Two** · 01-16-2011, 02:50 PM

So now I am curious, when would you / can you use the double fixture T. In my case I can see the drain possibly going in the wrong direction or as mentioned in a previous post it could an issue during snaking or other maintenance.

**Basement_Lurker** · 01-16-2011, 03:40 PM

Yes, I am curious as to why a double fixture tee cannot be used for the sinks either. And yes, a double fixture tee really is that expensive here in Canada. Maybe in the States they seem to stock it at the big box stores, but here it is a special order item, so by the time you factor in shipping from the factory, it does cost 50 bux.

**Terry** · 01-16-2011, 03:53 PM

In the United States, it has to be a fixture cross like the one pictured in hj's post.
You can use a double tee as a vent fitting, not for waste.
I realize that Canada is different, so maybe it doesn't matter if it can't be snaked.
We also use 2" where the two meet, not 1.5"

**Basement_Lurker** · 01-16-2011, 03:56 PM

a double fixture tee (what Hj's picture is showing) is different that a double santee (what most guys would use).

**Terry** · 01-16-2011, 04:03 PM

But not in the USA. Canada uses a double tee, the United States uses a double fixture fitting. Since this guy is in Canada, it doesn't really matter. He could use a rubber hose into a bucket and it would pass inspection.

Double fixture fitting for two lavs, for plumbing in 50 States, but not needed in Canada.

**shacko** · 01-16-2011, 04:17 PM

Originally Posted by Willie Two

So now I am curious, when would you / can you use the double fixture T. In my case I can see the drain possibly going in the wrong direction or as mentioned in a previous post it could an issue during snaking or other maintenance.

I don't know what Canada code says but in the U.S. if you are using the UPC (Uniform Plumbing Code) you can use a double fixture fitting (No. 5 fitting) at all three of your sections on your drawing, including the toilets.