Hi all - Planning a new bathroom on second floor, however the existing waste stack (for the first floor bathroom) is on the other side of the house. The new toilet would therefore be at least 20' away from the existing stack. I should be able to vent only a few feet away from the toilet, but the waste drainage is my concern. Is there any limitation on the distance a toilet can be from the waste stack? If it matters, I believe it may be a straight shot from the new toilet to the stack (no turns in the pipe, all down one joist bay). The new bathroom will also have a shower and sink. Thanks in advance, I've always found these forums helpful.

You may not have room in your joist spaces to make it 20'. Your pipe is going to be about 3.5" in outer diameter, you will need 5" of pitch in 20'. That alone takes up 8.5" of your joist space. Unless you have atleast 12" of vertical space in your joist space I would not even attempt this unless you can build a soffitt to run the drain in.
But, to answer your question, as long as you have proper pitch on the pipe and are properly vented 20' is certainly acceptable.

Hi Lee12, as CHayn says, you will need 5" of slope with 3" pipe and 2 1/2" of slope with 4" pipe. Also, CHayn touched on important issue: size of your ceiling joists. Please, measure and tell us what size they are. Soffit is the next option.

As far as the distance from waste-stack goes - you can go as far as you want. You are only limited by framing / size of your joists. You must vent properly. Post a sketch, we will take a look at that and tell you how to run your waste lines / vents.

As the experts have pointed out. You may place the toilet as far away from the stack as you wish.
However, unless you plan on building a false ceiling you'll likely find your drain line exposed before you connect to the stack.
Good luck, Tom

Thank you all for the help, my apologies for not thoroughly explaining all of the details. The drain/waste for the new bathroom will drop more or less straight down from the 2nd floor to the 1st floor (joists between the first floor and basement). At this point it will turn and run in the joist bay to the main waste stack. However, after about 7-10' this run will be over a basement with an exposed ceiling, so it will not matter that the pipe drops below the ceiling line after this point.

A further question, I plan on joining the new waste/drain pipe to a side branch to the main stack. I've marked in this image where I would probably join the new line. Any problems with this? The main stack is 3" pipe.



http://http://i566.photobucket.com/a...e12/stack2.jpg


If that image didn't work use this link

http://i566.photobucket.com/albums/s...e12/stack2.jpg

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Originally Posted by ;

A further question, I plan on joining the new waste/drain pipe to a side branch to the main stack.

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I can see no problem if the new bathroom group will be vented.
However I do see as problem with the "S" trap, (see image )that I see in your picture. How many of these are around? Cheers, Tom

Agree with Tom: looks good. Use combination of Y and street 45 to make the connection.

Again, thanks. Speedball, what are your thoughts on this S trap? This was intact when we bought the house, but it was definitely done after the original construction. Some previous owner installed a large whirlpool type tub in the 1st floor bathroom and all of this newer plumbing pictured is, I assume, from this remodel. The tub gurgles loudly when draining and I always took this to be a sign that something was wrong. Not sure who did the remodel (pro or homeowner). I'm a bit green with the plumbing so interested that you caught this in the pic. What do you think?

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The tub gurgles loudly when draining and I always took this to be a sign that something was wrong. What do you think?]

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Back in the 30's/ 40's all the tubs were installed with drum traps and no vent.*( Even in the house I grew up in). Every single one gurgled as it vented through the drum trap.
It's not going to hurt a thing if you leave it alone but 8if you wish to tear into it we can give you some pointers. Let me know, Tom

Tom,

Sorry for the delay in getting back into this conversation.

The house was built in the mid 70's, and I imagine the bathroom addition (with the S-trap) was done late 80's - 90's. There is no 'drum trap' as you describe it in your last post (I had never heard of one before, but looked a few pictures on the web). Do you think the gurgling has something to do with the S-trap? I am still not sure why this caught your eye? Would replacing it with a different configuration eliminate the gurgling? Thanks for all the help so far.

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The tub gurgles loudly when draining and I always took this to be a sign that something was wrong. What do you think

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A gurgle would indicate a blocked vent or in the case of your "S" trap no vent at all. The tub's simply venting through the trap. I wouls add a AAV(air admittance vent) just downstream of the trap, (see image) if it disturbs you. Good luck, Tom