Another DWV layout question

[FatsoPilot]

This is a bathroom basement, you can see the existing main stack and then vent (toward the outside wall) next to the planned toilet. The toilet will run straight into the main waste line going out of the house without a vent. I plan on venting/draining the sink straight along the wall to the auxiliary vent I already have. Can I vent the shower and bath together? What is the best way to vent it? Along the outside wall or can I come straight up after the Y to an inside wall and wrap the vent back around to the back vent? Are there restrictions on how far a vent can run horizontally? Anyone see an easier way to do this with less concrete removal? Cheers.

 

[Tom Sawyer]

The entire bath group can be wet vented but trap to vent distances must be correct.

 

[Sponsor]

 

[FatsoPilot]

Unfortunately, the bath/shower line is about an 11 foot run. With a two inch pipe wouldn't I need to vent it within 5 feet?

 

[Cacher_Chick]

The vent riser can come up from the shower drain line in any of the perimeter walls that are within the allowed distance.

 

[Terry]

There are plenty of walls that will take a vent in that layout.
If you go into a new home, you will see plenty of pipes in the walls that go up through the roof.

 

[Jadnashua]

While the vent must go up within the limits, 5' on 2" pipe , it can go horizontal (nominally at least 42" or 6" above the flood rim of the vanity you are also venting on that line) as long as it maintains the minimum slope. this should allow you to vent within the limits and still only have one vent rising out of the room.

 

[Terry]

The lav will need a vent there too.

 

[FatsoPilot]

The lav will need a vent there too.

Okay, I didn't think that would be the case with it being so close to the main vent/waste stack.

 

[Tom Sawyer]

Because the stack handles waste from above; that's why you need to vent the lav.

 

[hj]

Why does everyone think they are plumbers? The toilet SHOULD work without a vent, but if it were being inspected you would need one. your layout looks like you are trying to put 10 gallons of mud into a 5 gallon bucket. I have never seen a Roman tub installation where you had to climb into it over the end of the tub, and the "pinch point" between the sink and the corner to access the toilet looks pretty tight, and awkward.

 

[Tom Sawyer]

Well, it would only need a vent if your code says it needs one. If you are IPC you only need one somewhere in the building.

 

[Terry]

Washington State uses the UPC code. and yes the lav needs to be vented.
Also the tub and shower will need seperate vents that can only be revented at 42+ above the floor.
The toilet needs a space at least 30" wide with 24" in front of the bowl. Like hj mentions, it looks like a major problem getting to the toilet.

 

[FatsoPilot]

Thank you for the replies, they are much appreciated. The sink will be back further in the corner allowing more room to the toilet. The opening for the toilet is at least 36 inches, depending on how much insulation I decide to use on the outside wal. The bath shower combo will be a contained Japanese type unit so you can wash and then directly enter the tub from the side.

There use to be a toilet and shower in this area which was put in before I owned the house, I think that was when they put in the 2 inch copper vent. Venting the toilet will be easy enough coming straight up the back wall. What would be the easiest way (and least amount of concrete hammering) to vent the shower and bath? Can the existing 2 inch vent handle the sink, lav, shower and tub? I'm not totally set on the layout, I'm just trying to fit everything in the space I have with the least amount of concrete work. Thanks for the help.

 

[Terry]

The laundry tray downstairs is not plumbed right. The trap arm can't be turned up with fittings.
If you have a 2" vent going up through the roof, that will be large enough for the entire downstairs bath. The vents for downstairs could combine at ceiling level. 42" above the floor works too, but sometimes it's easier to do it higher then that.

I would hire someone with a wet saw. Less damage to the concrete, no dust, and nice clean cuts to pour back to.