Moving bathroom to other side of my house ?

Hi all, my first time posting so I do apologize ahead of time if I mess up and make things more complicated then they should be. lol

I plan on moving my bathroom from one side of my house to the other side. I do have a couple questions.

- 3" abs running at a 1/4 inch per foot drop(in crawl space) from new toilet,sink,shower to existing stack (estimated distance will be approx. 35 feet). Is this possible ?

- if this is possible I have a 3inch vent at the stack end now I would leave that there and have all fixtures in new bathroom tied into a 2" that I have fed up through the roof.

quote; - 3" abs running at a 1/4 inch per foot drop(in crawl space) from new toilet,sink,shower to existing stack (estimated distance will be approx. 35 feet). Is this possible ?

Yes, in concept it IS possible, but we do NOT know if it is possible for YOUR installation.

Thanks for your response. I just like getting some confidence here. lol

I was just wondering if that distance would be too much, would the solids going down the toilet eventually slow enough to get stuck in the drain under my house?

Now , would a 2 inch vent running from below the floor up through the roof for my new bathroom be sufficient ?

I am leaving the original 3 inch vent which is attched to the main stack that runs up through the roof as well.

Would I have any venting problems.


I am going to try and draw this out and attach it as well to make things easier. Thanks for your help.

Just make sure you don't go horizontal with the vent for that lav until you're 6" above the flood level rim of the sink or 42" from the floor...

Attachment 15659


would that be better

Now just make sure you trap arms are long enough to avoid s-trap issues, and you should be good to go.

I think the connection to existing sewer, as well as properly supporting all of that 35' of pipe is the more important factor here, that is a basic bathroom.

Also, I would add a cleanout where the lav is, in the vertical piping, the end-of-line cleanout should suffice for the 3"...

Just nice not to have to remove the trap if there ever was a clog.

The plan is fine, assuming you use wyes and sanitary tees where they belong.

So basically you would use wyes everywhere except where you are connecting a trap arm to a vertical pipe.

Use a wye and street 1/8th bend, or a combo if you can find them.

Well thank you, your advice is greatly appreciated. To avoid the s-trap situation how long would that horizontal run from the trap to the vertical drain have to be?

This drawing is a real quick one I did up and they are longer then what they look in the pic. Probably about 12" long, would that be fine?

And there is also y's instead of t's where you guys talk about. I was more concerned about the length and if it would be properly vented with just two inch.

12" is plenty long, the rule is 2x the pipe diameter.