Putting in a new bathroom as part of an addition. Currently trying to work out the venting details, among other thngs...

Is the configuration shown in the following picture acceptable? From what I've been able to find so far, it seems like maybe it would be allowed, but it might be at the maximum distance. If that's the case, should I be worried? Toilet drain is 3", vent is 2". Thanks.

http://i566.photobucket.com/albums/s...toiletvent.jpg

Hi Lee...

Sorry, but that setup won't fly as you are discharging an unvented toilet past a shower drain and the toilet would siphon the shower drain looking for air.

If I am correct, you are picking up the toilet and the shower using only the one vent, right? If WET VENTING is allowed in your area then you may be able to use only one vent but the configuration would need to change in such a way that the 2" vent would come off the 3" drain line just after the toilet but the shower drain would come off the toilet vent itself (why it is called wet venting).

If wet venting isn't allowed in your state then using your setup as drawn you would need to add a 2" vent juat after the toilet connection and connect it back into the shower vent at a minimum of 42" off the finish floor.

More questions? Let me know...

Mark

PS: Where is the sink in all this? If the sink is involved in the plumbing drains/vents let me know as this gets more involved. Also, don't forget to add a PTRAP to the shower drain.. right?

Hi Mark - thanks, I really appreciate the help.

I will post a picture this evening that shows the complete layout of the bathroom and better details for the plumbing. The original picture is a bit misleading, the shower and toilet drains would be separate until they reach the wall, at which point they would come together with a 2" vent going up and a 3" drain going down into the basement. I just wasn't sure if a vent 6' away from the toilet was okay (my first of many questions!). I've done a lot but never any plumbing to speak of. Certainly want to make sure that everything is correct. I'll draw something up tonight that shows the total plan. At this point only some of the interior walls are up and the sub floor is only temporarily down with screws, so I should have some flexibility in that regard.

Regarding the sink - it will be on the opposite wall to the toilet/shower and would have it's own vent and drain. I will certainly have a trap on the shower, although I didn't show it on the last drawing. There will be some issues with it however, as you will see...

I think that my main obstacle with all of this will be the floor. The bathroom is sitting over a section of the original house (not the addition) which has only 2x6 floor joists. I have beefed these up substantially by sandwiching the original joists with 2 layers of plywood and two extra joists each. What I have now are essentially 6" x 6" beams at 16" OC for joists. This certainly did the job for stiffening up the floor, but I am still left with only 5.5" of under floor space for pipes. Not sure if that will work or not for everything. I came across a 'hepvo' trap that I thought might work for the shower if it is allowed (most of the sites I've found that mention it are related to RVs). If it's allowed in residential situations I think it would work, although I'd want to get opinions.

Sorry for the long post here, hopefully with the picture it gives an idea of where I am at. Certainly appreciative of any advice - thanks.

Under UPC, we can run 5' with 3" toilet pipe before installing vent. It is 6' for 4" pipe. However, Mark was correct in his response regarding venting past shower...

Milo - thanks for the info, I know I had seen 6' somewhere but I guess it was for a 4" pipe - thanks for the clarification.

The following pictures show the total plumbing plan as of now. Red pipes are new, the black stack on the far left is where everything will tie in. The gray part is where the addition has been built. The third image shows the new idea for venting the toilet. Any comments about the overall plan are appreciated as I am new to the plumbing world. Thanks.

http://i566.photobucket.com/albums/s.../floorplan.jpg

http://i566.photobucket.com/albums/s...2/longview.jpg

http://i566.photobucket.com/albums/s...oiletvent2.jpg

Hi Lee...

Lots of issues above but before I go into any of it I need to know if wet venting is allowed in your state, OK? Post back and let me know...

And why is the sink drain running all over the place instead of coming off the toilet drain pipe... answer this, too?

Mark

I don't think that wet venting is allowed but I can check, there may be exceptions. I am in PA, IRC is the code for my area.

In the pictures above the floor joists run left to right and they are only 2x6. I'd like to avoid drilling any holes in them which is why the sink and toilet/shower drains run separately to the wall. I didn't plan for them to connect in the wall because I thought I'd have to notch a number of load bearing 2x4 studs. After dropping down the wall they turn to come across the basement ceiling. Half of the basement is finished, the other half is not. I just figured I'd push the pipes through the finished part and finally join them together over the unfinished part. In general, I have everything running off toward the addition first because that's the part that's unfinished. Going more directly toward the soil stack would involve disrupting finished living space below. But again, if it's preferred then I will explore that route.

One thing I had thought of is that I could have the pipes come together in front of the load bearing wall and just pad the wall out an extra few inches to allow drywall to cover everything. It's not really my first choice but if it would be preferred for plumbing reasons it could certainly be done. Please let me know what I need to address, I'm a little worried by your 'lots of issues' comment... (gulp). Am I on the right track at all?

If I run the pipes directly toward the soil stack (rather than toward the addition first), I was also worried about having enough room in a 2x6 space for proper slope. If I go toward the addition my longest distance from a fixture to the wall is 6'. If I go the other direction my max distance would be around 12'.

HI Lee...

PA code says that you can have a 3" drain line for a toilet up to 12 feet from the vent. For comparison, in Milo's area it's 5 feet and in my area it is 8 feet, but the fact is that in your state it is 12 feet (table 906.1) so that works really great for you... read on.

Wet venting is allowed in PA, but you can't utilize this concept because your joists are so small. Therefore, I'm thinking the easiest solution here would be to pipe this up as I have drawn below (see image). I did not include the double sink in the drawing but will present my ideas on that at the end.

Here, the toilet needs its own vent and the shower needs its own vent. By taking the shower drain off BELOW the toilet drain fitting you can run the shower drain and vent and you can run the toilet drain and toilet vent and simply connect the 1.5" shower vent back into the 2" toilet vent at 42"-48" off the floor and you would be all set with this section.

Continue the vent upward and through the roof and branch off to pick up the double sink vent to finish the venting. The vents always pitch back from the vent stack toward the drain so that any rain water (or condensation) can fall back from the vent to the drain via gravity.

Use a 3" long sweep 90 when going from horizontal to vertical. Use any 3" 90 that fits for the toilet drain. Use a 2" PTRAP without cleanout for the shower drain... should just fit a 5.5" joist. Install a 3" test tee cleanout in the drain line where it is readily accessible.

In terms of the sink drain, it's a bit of a run, but at 5.5" joists you don't appear to have choices...I guess? With that being said, I think you should come off the 3" drain line using a 3"x2" WYE fitting (no sanitary tee fittings on horizontal drainage pipes). Run 2" to a 2"x1.5" double sanitary tee fitting for the sinks and run an 1.5" vent up to join with the toilet/shower vent. All 90s used on the 2" sink drain need to be long sweep elbows. Install a full-size cleanout up under the sink and down off the main drain line. Hang the drain and vent piping every 4 feet. In PA, 3" pipe gets 1/8" pitch per foot and 2" gets the 1/4" per foot.

Hope all that makes sense. Questions you just let me know, OK?

Mark

Thanks Mark, it sounds like you see a doable situation which makes me a little relieved!

On your drawing - the main central vent and drain where the toilet and shower join, would that be in the wall behind the toilet? Or still the wall off to the right (like what I had drawn)? Just want to make sure I'm looking at this with right perspective.

Wasn't quite as bad as it first appeared... ;)

To answer your question, all goes off to the right behind the shower... lines up in the joist bay(s) this way, right?

Of course, sorry for the confusion, think I got it now.

For what you wrote about the sink drain, would it still follow more or less the same path I showed? Thank you for all of the specifics on the fittings, that would have been my next line of questioning!

Also, you show 1.5" for the shower drain and 2" for the sink drain (with 1.5" trap arms) - for some reason I thought 2" was needed for the shower? Is that not the case?

Nope... I show 2" for the shower drain and 1.5" for the shower vent.

In the drawing I only show the sink vent, but I don't label the size (although it should be 1.5"). The 2" next to the vent is meant to show that 2" continues up and through the roof.

2" Ptrap without cleanout for shower.

Sinks get 1.5" traps at each sink. 2" sink drain is really only because you have so many turns and such a distance that 2" will help keep the pipe from clogging. Shortest distance possible is best solution!

Mark

You are right, my mistake.

So shower - 2" drain, 1.5" vent
Sink - 2" drain, 1.5" traps, 1.5" vent

Any reason to not use 2" for the vents? (only because I already bought a bunch of it)

Nope... 2" is fine, too! I'm off to work now, pop back anytime!

Great. Mark, I cannot thank you enough man.

I will draw this up again tonight and label all the fittings. Just to make sure that I have everything correct here before buying anything else.

All right, getting closer here I think! How's this look? I marked two spots where I could easily place cleanouts, is that enough?

http://i566.photobucket.com/albums/s...pwfittings.jpg

Install another cleanout at the 3"x2" wye off the main and I think you look pretty good here!

:)

Great! I'll pick up the rest of what I need today and plan to get started this weekend. I'll check back in when something comes up (bound to happen... ). If not, then probably when it's time to think about water supply. Hopefully that is a little more straight-forward. Mark, thank you again - you have really been a great resource!