Does this dual bathroom remodel look correct?

[Paul S]

Doing a renovation on our home and redoing the bathrooms. I am a DYI and this is my first time doing DWV work. I have studied this pretty thoroughly but wanted a professional look before I commit further as I need to get some of the walls up. I used Google Sketchup for the first time to do this and some of the pipe connections are a little off but I think it should be an accurate representation. I think I might have been able to make some shortcuts and reduce piping but decided to error on the conservative side. Some of the corners are incorrectly represented as short sweep because I could not find the correct models online. Appreciate any feedback.

 

[PorcelainVacation]

You can wet vent toilet #2 with the shower vent if the vent is 2" or bigger.

 

[Sponsor]

 

[Paul S]

I will look at wet venting toilet #2 as the shower vent is in fact 2" as suggested. Thanks for the input. In the mean time, I did find some models online for large sweep wyes and bends. I also corrected two sanitary tees that were upside down in the picture. Surprised no one else caught that... So I think the drawings are now accurate. Any other comments welcomed.

 

[Highlander]

Not a plumber but here's a rambling of a few things I've noticed...

First off, cool drawings !

There's one at the end of the 3" run but you'll wants add some more cleanouts for the laundry and the bath sinks (above the San-tee in all cases, can be hidden in vanity cabinets). As it stands, for toilet vents as well...which brings up...

There are short sections of more or less flat dry vents (toilets, part of shower 2), might not be best long term if you get a clog and "stuff" backs up in them, there will never be any water flow to wash it out. Might not get approved either, although looks like you've made the effort to tilt the combos to provide some "verticality". Maybe you take a slightly longer path for the sinks and dump each in its respective toilet line so it's wet venting them?

Lots of complex venting in the toilet wall, which means lots of drilling etc... might be easier to go vertical and join things in attic (assuming there is no other floor above). Or at least combine the shower 2 line with the toilet lines rather than dual runs. Both work but lots of horizontal holes means weakened partition walls, not ideal if you ever plan on doing any tile on them.

Probably can't get the right fitting in Sketchup but where the laundry/shower line hits the main should probably be a 3x3x2 combo and not a 3x3x3 with reducing bushing, will be easier to completely clean out.

I forget the details but there was discussion about recent code changes and laundry lines having to hit a 3" line sooner (because new machines pump out much faster), not sure it applies here, something to research or check with a pro. Wouldn't be much more expensive to have a 3" "side line" from the main and dump the 2" into that.

Good call on avoiding the shortcut of wet venting shower 1 with the laundry (wet vent only within a bath group).

 

[Cacher_Chick]

All of the horizontal drain connections must be made with wyes. A sani-tee is only for use when transitioning from horizontal to vertical.

I would also install cleanouts on every vertical line that is going down below the floor.

 

[Reach4]

I suspect there is a simpler way to handle the drain out of the washing machine box.

 

[Paul S]

Thanks for taking the time to review and offer suggestions!!! I appreciate all of the feedback !!! Replies below:

1. I suspect there is a simpler way to handle the drain out of the washing machine box - Yes, looking back now it is more complex than needed. Simplified in version 3 plans below.
2. All of the horizontal drain connections must be made with wyes. Correct, this was just an error in not being able to find the right models in sketchup. I corrected this in version 2 and 3 after finding more better models. Still not perfect though as I could not find a 3x3x2 combo.
3. I would also install cleanouts on every vertical line that is going down below the floor. Good input. Thanks. I added them in for the two sinks. For the laundry, wouldn't it be just as easy to clean through the outlet box itself versus having a separate cleanout plug or am I missing something here? Since its behind the washer its probably no big deal to add it.
4. Maybe you take a slightly longer path for the sinks and dump each in its respective toilet line so it's wet venting them? Unfortunately there are other obstructions under the subfloor so this is the best route.
5. Probably can't get the right fitting in Sketchup but where the laundry/shower line hits the main should probably be a 3x3x2 combo. Correct, I planned to use 3x3x2 combo but could not find the right model. Tried unsuccessfully to make one so gave up. Was not planning to use a reducer.
6. Wouldn't be much more expensive to have a 3" "side line" from the main and dump the 2" into that. Excellent suggestion! Done!
7. might be easier to go vertical and join things in attic This area has a dormer roof and I was unable to show the angled walls in the first plan version. There is no attic here to get to. The walls they would be run in will be added to make new vent line easier to run and also to allow the toilet to be brought further away from the sloped wall to provide more height.
8. Or at least combine the shower 2 line with the toilet lines rather than dual runs. so, would be interested in feedback on this one. Reference guides note that when stack venting, never place a toilet above the other fixtures due to the larger discharge. To avoid doing this, I had a separate line for shower #2 which dumps into the vent stack above the two toilets. Since it was a new wall I was adding as noted in 6 above, there would no obstructions to worry about. If there is any chance of the toilet sucking shower #2 trap dry I would rather run the extra line. PVC pipe is cheap to run now before tile and everything else is up... Later it gets really expensive to correct
9. cool drawings. I am amazed by the Google sketchup application. I saw someone else had used it so I downloaded a 30 day trial version for free. It took about one day of playing to get the hang of it but had the majority of the basic room laid out and first crack at drain locations on day two. Had completed plans and started fine tuning errors and such by day three. Obviously it will be much easier to use next time. Since I am always doing some project, it is a handy software package and incredibly powerful.

New plans below with changes noted in red. I also added in a test plug after all the new work before entering the main line so I can leak test the new construction. Appreciate all the suggestions! Paul

 

[BruceL]

Nice drawings.

Not a plumber, but a couple questions.

It looks like your toilet vents run horizontal below the subfloor? My understanding is you can't do that.

I think the drawing has the ordering wrong between the washer and shower 1, I think you intend the vent to hit the shower drain first and then have the washer come in, whereas right now if I read the drawing right you have the shower wet vented with the washer and then another vent. Regardless, I think 3" would make this technically compliant (if not wet vented), but my inspector really did not want to discuss washer and tub sharing a drain. I would clear it with the inspector first, but in my case I know I would have been told to take the shower drain and run it back to the rest of the bathroom group.

Bruce

 

[Paul S]

Bruce, thanks for your time to review the latest update.

Q. I think the drawing has the ordering wrong between the washer and shower. Yes, you are correct. I originally had it that way. Then Reach4 had suggested simplifying that area which was good input but when I did, I inadvertently reversed the order. Thanks for catching that as I completely missed it. I updated it as noted but including the increase to 3" line to cover high capacity washers as suggested by Highlander.

Q. It looks like your toilet vents run horizontal below the subfloor? My understanding is you can't do that. Yes, the vent runs a short distance before hitting the vent stack. It would intersect the 3" run at a minimum of 45 degrees and have a slope of 1/4" per foot. This method appears as one of the two acceptable venting methods for a toilets in Renovation 4th Edition as shown (not that this makes it correct). Any professionals have any comments?

 

[Cacher_Chick]

Most places would not allow the vent to run horizontal below the flood rim of the fixture unless it were a wet vent. When there is a backup, the waste would go into the vent and even after the drain system is cleared, the solids could remain in the horizontal vent.

 

[Paul S]

Okay, thanks Cacher_chick, will spin the toilet drains parallel to the back wall, will take vent pipes at 45 degrees off 3" drain and then go vertical through the back wall. No Horizontal Runs Below The Flood Rim

Here are final drawings. Unless anyone sees anything else, I will call it a wrap. THANKS to all who offered input.