Help with rough in...

I thought this post might have been buried because I hadn't updated for a while...

I've attached two photos and would appreciate any advice on them. I was unable to fully draw everything I wanted - like the vent from the sink coming around to a 3" vent pipe near the toilet.

Here's what I'm struggling with:

1) Where to locate the 3" vent through the roof. This is an unfinished attic space so the ceiling dimensions slope. Since the vents must be above the highest fixture it might need to be located towards the center of the room.

2) Where do I vent the toilet? If you are standing in front of the toilet, the drain for the lav turns left and then must go through a floor joist and straight down a vertical wall. I drew a plan using two 45's and a bit of straight pipe, but that might be wishful thinking if I actually want it to go down the wall without widening it or building a little soffit.

I just can't tell right now if I'll be able to get a vent (especially a 3" one) to the lav dwv before it turns down the wall. I have a few ideas, so I'll make a sketch.

3) If I take out the 3" vent pipe I now have coming from the lav drain before it turns down the wall, can I put a vent for the toilet in that vertical wall with a T/Y combo? It wouldn't be very far from the toilet, but it would be below the toilet. I'll sketch it.

All advice greatly appreciated! Sorry if the pictures are bad. I had a heck of a time getting my scanner to scan within all the ranges the site wants.

I'm having trouble following your drawings but I'll give you some advice to see if it helps.

On the toilet, take the pipe leading from the flange straight back to the wall the tank is against and turn up a tee, whether you are venting this bath group on 1.5" or 3". From there, you can install a wye to pick up the vanity/tub/shower.

Take the vents off of those fixtures up to 42" and you can connect to the vent coming off of the toilet.

Anything above 42" you can 90 the turn of direction. Under 42" you must not turn direction of more than 45 degrees. Otherwise that is a code violation of flat venting under 42".

In my area the vent must increase to 3" 18" before penetrating the roof, a minimum of 12" exposed outside of the roof, dictated by roof pitch.

rough in help

First of all your drawings do not help explain your lay-out,according to the International Plumbing Code (IPC) to vent your fixture group I am assuming that you already have a bathroom in the house with a full size vent going thru the roof 3"or 4" so the IPC says your vent only has to be half the size of the waste on this new 2nd floor bath,the vent if you are using 3"pvc for the closet bend and the waste stack to the basement. The vent piping can be 1.5" pvc pipe,you must increase the vent to 3" about one foot below the roof-line and one foot above the roof if,. it is not possible to tie the vent backinto the existing DWV at least 6"above the flood level rim of the highest fixture,which would be your sinks.I would need to see just a rectangular floor plan lay-out of your fixtures then I think I could help you better understand what you must do.

fixture layout and a question...

Okay, thanks for the information. Here's a sketch of the fixture layout in the bathroom for tbplumbloco. I'm not tying into the existing 3" vent in this space. It's like 20 feet away. There will be a new pipe through the roof. I'm not sure where I want that vent to got through the roof, however. Keep in mind, the roof up here slopes in a triangle. The farther out to the sides you go the less height there is.

My big source of confusion is really about venting the toilet. The standard thing to do is to run a pipe to the wall behind the toilet, but because my floor joists run in two different directions I was trying to avoid drilling the joist to put it in the wall right behind the toilet. So I was just planning on running a straight pipe vertical off the toilet choler, then bending it left of the toilet instead of behind it and trying to vent from there.

Two questions:

1) I didn't plan to run a pipe to the wall right behind the toilet because I'd have to drill through the floor joists there and I was trying to avoid that. My house was built in the 1920's and so the floor joists aren't to code. I'm having them sistered up to code, but I'd hoped to avoid drilling them. We're planning on putting a cast iron tub in the bathroom, so I didn't want to drill the joists behind the toilet. As you can see in the diagram, the joists run east/west in the bathroom. But the wall I'm sending the plumbing down to the stack in has joists running the opposite way, north/south.

Are you saying that I can drop a bit of straight pipe off the 3" toilet choler, put in a Tee of 1.5 to 2" back to the wall behind the tank and then connect that above 42" to the rest of my vent pipes that run to a pipe through the roof? I'll just barely have the height to get 42" from the floor. That's what I need, right? 42" from the floor?

I suppose if it's only 2" I can maybe drill the joist.

2) I'm again thinking about AAV's. Can you use one with a toilet? How would that work? Would you just need to run a pipe behind it with the AAV hidden behind the bowl so you have access?

Or maybe I'll just use AAV's for the sinks. That's easy enough. Just install them right behind the p trap and then concentrate on venting the toilet.

Any further advice is appreciated greatly.

rough in help

Where is the sketch?Any-way you can place the 3"closet bend in any direction you need to go,install a 3x2 wye horizontially before you go vertical with the 3" waste,fom the 3x2 wye go back and pick-up the 2 sinks with a 2" wye on up to a 1.5"cross, the trap + waste pipe will be 1.5",extend the 1.5" pipe vertically out of cross (do not forget c.o. above the cross)this wil be your vent pipe thru the roof,1.5" vent must be increased to 3"12" above + below the roof line,NOW from the back outlet of the 2"wye connected to the sinks run 2"pipe to the bath tub1.5" trap if the distance from the bath p-trap is less than 6' you do not have to individually vent the tub.This is the wet vent method approved by the IPC,the vent from the sinks also serves the toilet as well where the 3x2 wye connects downstream of the closet bend.I also would like to add that i would run the 20' of vent to the existing dwv if physically possible rather than make another penitration thru the roof.

Question...

Let me just say, many thanks right now for your advice.

I follow your plan. So I'm basically connecting two wye fittings, one on top of the other, to a T.

This is an elegant plan. But I just uploaded the sketch that didn't go the first time. I think you envision all the fixtures on one wall, which is typical for a bathroom. Of course, mine isn't typical. Take a look. The toilet is on one wall, the sinks the opposite wall, and the tub in the center of the room!

It's bizarre, I know, but we can't dormer this area of our attic as it's in a setback and we'd need a zoning variance. So we're trying to get two sinks and a tub you can actually use for two people who are 6 feet tall. The other thing to remember is that there are windows behind the tub, so nothing can really run back there, either.

I just made another sketch showing the layout. If you'd care to keep working with me I'd really appreciate it.

rough in help

O.K. the floor lay-out helps,but it would be nice to know the dimensions of the room so the wet venting method that I described earlier will work.The way that I see your present drawing,sinks on North wall,tub on the West wall and the toilet on the South wall.You can run the closet bend north up to 10' and then install 3x2 wye then a long sweep 3"90 going east to the joist that you will have to drill and then beef up with scabs or sister joists,out of the 3x2 wye install 2" 45 going west,as you move west install 2"wye with a 2"45 to pick-up sinks,reduce to 1.5" cross as described earlier,continue to move west with 2"pipe to pick-up tub,tub trap will be 1.5".You wil have to drill holes if needed to connect the 2" waste pipes.I would draw you a diagram,but I am a better plumber than computer geek

Joist layout for this room...

Checkout the first layout drawing. The joists in the bathroom run east/west. So turning the toilet dwv north would mean drilling every joist in the room. If we turn the toilet drain east it will go inside the joist cavity until the bedroom wall. There the joists go north/south and we'll drill through one.

It's not a big space, just enough for what we want to do.

Thanks for your time, man.

rough in help

O.K. I have the picture,turn your 3"closet bend going east to make the vertical drop to the basement?Drill thru the joist and install the 3x2 wye before you go vertical,install a 2"st.45 in the wye,it should be going north parallel to the joist running N+S,as you are going N install 2" wye with 2"st 45 going west to pick-up the tub,continue going N with 2"pipe to pickup the lavs as discussed before,if I have it right you will drill one hole for the W/C and one for the tub and one for the lavs all drilled thru the one joist running N+S just remember to support that joist,all piping that I have described will be installed horizontially,except riser leading to lavs and continuing for the vent.

I'll draw the final picture...

Alright, that sounds like a plan. I'm going to draw it and post it to make sure I have it right.

Thanks again. You've been a huge help to me and my family.

Sketches based on your suggestions...

Okay, here are the sketches based on your ideas.

I'm a bit confused about what to do with the vent lines from the sink after I turn the drain towards the drain for the tub and the w.c. I marked it on the diagram, so if you can explain a bit I'd appreciate it. Do I just run the horizontal vent line in the west wall and then send it vertical into a Tee for a vent closer to the tub and W.C?

Secondly, I wrote the room dimensions on the diagram with the w.c. and the tub. It's about 12+ feet to the tub from the dwv to the dwv lines heading north. The w.c. will be about 7feet from the lines on the north wall. Maybe a bit less.

Does the rule of being no more than six feet from trap to vent apply in this wet vent? I checked my IPC book but it was unclear to me.

I drew the diagrams separately, as they are in different planes (one in the floor and one on the wall).

Thanks for your help. I'm hopefully almost there.

rough in help

I looked at your sketch,you are on the right track with the closet bend and the 3x2 wye,but you did not quite understand the venting for the lavs,run the 2"pipe out the 3x2 north parallel with the N+S joist now follow this closely.Turn the 2"pipe west with long sweep 90 or 2 45's,your thru the the N+S joist and running parallel with the E+W joists continue to run the 2" west,now install a 2"wye with the 2" st 45 running N and the back outlet of the wye heading west for the tub.Now go back to the 2"45 going N center it between the two lav sinks,run 2" pipe N horiz.come up thru the floor on the wall the lavs are on,approx 18" off the floor install a 2x1.5 " cross reduce the top outlet of the 2"cross to 1.5",stack a 1.5" clean-out tee there ,the top outlet of the clean-out becomes the vent,run it vertically thru the roof as discussed before,now what is very critical in the wet vent for the tub go back to the back outlet of the 2"wye leading to the lavs,where that 2"pipe running back to the tub must connect to that 2"wye for the lavs at 6' or less,if you can not install the pipe with-in that distance you will have to individually vent the tub,which can be done by laying 1.5"tee on its back going vertically and tieing into the vent for the lavs.The wet vent is established by the lavs emptying into the 2x1.5 cross and that horizon.run to the 3x2 wye is the continuation of the wet vent which also vents the WC keep the horizontial runs 2"and you have a good venting system for that fixture group.Now some one needs to teach me how to put a diagram on this board.

rough in help

I forgot to tell you,out of the 2x1.5 cross run your waste arms to each lav and make sure that you are 5' or less from the vent and stub out.

When you respond to a post there will be a "manage attachments" button underneath the box you are typing in. From there if you have the diagram already scanned into your computer, all you have to do is click "Browse" and it will open up "your pictures" or "your documents" file folder on your computer.

From there you find the image you want to load and click upload.

Your image should show up as an attachment before you click the submit button on the reply screen.



Here's a pic of my cat......all I did was hit browse, upload and then submit. This came from my computer

Diagram would help big time...

I've enclosed a quick sketch of the wye fitting I did wrong heading to the tub and then north, through the floor joists running east/west, to be centered between the sinks. Am I on the right track?


I'm working on a sketch for the sinks. But if you want me to send the 2" pipe heading west to the tub north between both sinks, then I have to drill through every joist in the way. If it has to be done, so be it. But I am planning to have a heavy tub up here. The less I have to drill floor joists, the better. Is this a change in the original plan because of the room dimensions I just stated or was this part of the original plan? Maybe drilling the east/west joists was inevitable.

Also, I'm having some trouble sorting out the venting diagram for the sinks. I'm just not as visually talented as you plumbers are! If you could pop off even the most basic diagram to give me an idea It'd be a huge help.

Sketch of Sink wet vents...

Okay, here's my sketch. It's much simpler than I thought (assuming I have it right).

I think using the cleanout Tee on top of the cross threw me a bit at first. Why not just use a straight pipe there? Isn't the cleanout just capped?

This sketch is what you would see if you looked at the wall from standing in front of it.

Let me know if I've got it when you get the chance. Again, many thanks for you effort on this.

rough in help

Your wye must be in the direction of the flow towards the the 3" waste ,yes you may have to drill thru an additional joist so that the 2"wye picking up the sinks on the side outlet w/a 45 which head N,the back outlet of that wye will run west to the tub.That wye must be 6'or less to the trap of the tub otherwise you will have to revent the tub.Rugged I am having the same problem comprehending sending this diagram as coach is having with visualizing the isometric drawing.Coach you said you have a copy of the IPC, study the section on wet venting and focus on the iso drawings.My teen-age daughter is going to give me a computer lesson,have to sign off now 5:45 am eastern comes quickly

One last question here...

I just read this article stating that the water closet must have it's own vent and not a wet vent. Is this per local codes or IPC? Or not true at all?

Thanks.

Here's the quote:

"As shown in figure 8-22, the lavatory should be individually vented. This is necessary to prevent loss of the trap seal through indirect siphonage."

rough in help

Just noticed your drawing for the lav sinks,you do not need the extra tee to the traps of your sinks,study the drawings in the IPC

one last ?

I do not know what you are reading from.The IPC has a whole section on wet venting,which is the standard for plumbing natiowide,but there still are jurisdictions that do not recognize this and have there on local code policies,you better check with your local plumbing inspector or this fixture group would have to be laid out a different way than what I have described.