Converting sink drain to tub

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We were able to remove all of the CI all the way down into the basement using the soil pipe cutter. I really don't know why we didn't try that a long time ago as it was pretty simple. On only one of the cuts did it "crush" one side of the pipe (cutter prob wasn't straight) but the last cut in the basement was clean enough. We left about 30 inches of CI coming up thru the concrete and put the cleanout at the same height as the old one... about 4 ft.

So we will turn the tub around, which will also orient the tub user for a better view outside the window (once installed).

I am curious what it means to "Muriet" those electrical connections. I can get to one end of those cables (they followed the CI down by the exterior wall for lights and outlet) but can't get to other end. I was planning on putting a round junction box there with an access plate in the ceiling below.

Yesterday afternoon stopped by Lowes to get new fittings now that most our plumbing planning is out the window and was fortunate to get the assistance of a retired plummer with 40 years experience. We were the only customers and he took the time to help us pick out the correct fittings. Laid them out on the floor for us and was so helpful I thought I was dreaming.

It is interesting how much more helpful they are when I have my wife with me.

We will be switching the drain for the tub to 2" and once we get it all laid out I'll be spamming the thread with some more hi-res picts.
 
Had a bit of a mishap this morning when I lost my balance and found myself in both the bathroom and the family room below.... :(

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Though my leg got fairly nice contusion, this was probably not all that bad as I discovered that the cross-wise support that is part of the box around the old closet bend, (the one with the hole) was not actually attached AT ALL to the joist to the left. It is also split in two. It was also hanging down about a half an inch from the other joists. So I jacked it up with an 8' 2x4 and some plastic shims and drove some 3.5" screws into it. Not sure if I'll replace it. Might just screw some more 2x4's on the side of it.

We did decide to turn the tub around, putting the drain much closer to the main drain (whatever that is called) which is now all 3" PVC to the basement. There's not a lot of room between those joists so will raise the drain up about 1 - 2 inches. (Tub has 3/4" support at drain end which increases to about 3 at other end). Using 2" trap and PVC until it joins a 3" 90 deg elbow that joins the double sanitary Tee with a bushing.

I'm hoping this will work okay.

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The large amount of fall on the 2" pipe between the trap and the 3" 1/4 bend forms an S trap. It needs to drop no more than 2" from the trap to the vent, so that even under heavy drain load, the entire 2" pipe at the point where it connects to the 3" cannot fill up with water and stop air from getting back to the trap.

Also, double sanitary tees, also known as sanitary crosses, are falling into disfavor in the plumbing industry. When the toilet flushes, it will often throw water and waste across the fitting and into the drain pipe on the other side. IPC prohibits their use for back to back water closets or washing machines. Another issue with sancrosses is that if either drain needs to be snaked, the snake will usually jump straight across the fitting and come up in the other fixture.

I would recommend a 3"x3"x3"x2" side inlet sanitary tee for your application.
 
I can increase the length of vertical 2" to the trap from the tail pipe to minimize that drop.

We really want to move the tub farther to the left away from the main stack, but don't want to cut any more holes thru the joists. But would that really be so bad to drill one hole? I would be on the short joist. I could put bunch of long screws to strengthen the connection between those joist sections. Or even long bolts with metal plate of some sort on each side?

That's a good point about snaking, especially as the toilet will be fairly close. Thanks for pointing that out.

I was thinking something like the 3x3x3x2 would be helpful but could not find it where we were shopping. Will make trip to Ferguson tmrw and see what they have.

I have a feeling it would not work, but what about a fitting on top of what would instead be a sanitary Wye? That is, stack to Wye's on top of each other? If you flush toilet while the tub is being drained there would be no vent, right?
 
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As far as drilling holes through joists, my answer everyday on a jobsite and my answer to you is "I don't do it unless I have a structural engineer tell me that I can". I am just not going to OK something like that, either in person or on the internet. I do not have the knowledge necessary to make that call.

As far as fitting arrangements, if you have the room in the floor system, you could use a 3" sanitary tee down low for the toilet, then a 3"x2" sanitary tee directly on top of that for the tub drain. Do NOT use wyes in this situation, as those fittings would break the hydraulic gradient to the vent, in the same manner that the excessive fall in your previous picture does.
 
It seems logical that the 2" p-trap would be better but the cleaning action of the water draining through it would be better if you had 1 1/2" p trap.
That looks good. As far as the vent for toilet being effected by draining tub. Not a problem.
So when the career change going to be official
 
1.5"? You're trying to make me nuts, right? That'll be easier to squeeze all that in. Since I could cut into the ceiling from below if needed, would it be worth it to use a trap with one of those rubber cleanout plugs? Or is that just one more place for a leak to develop?

Career change? To what? Photographer? At 53, not sure my back could handle doing this all the time.

I'll stick with my job with the National Weather Service as a meteorologist/programmer. Much better benefits.
 
You can snake the trap through the overflow if need be. I shy away from unnecessary threaded or gasketed joints.

As far as what you have in you latest picture, go ahead and glue it together.
 
Ya'll are confusing me! Inch and a half or two inch for the tub trap?

I'm hesitant to glue much of anything until everything is laid out as we'll probably change the layout again five times.
 
Either way will work.

Mr. David prefers an 1 1/2" for this installation, and gives a reason. I would prefer a 2" trap, because I think that it is less likely to catch hair and soap scum. I have no real evidence for my preference.

Either way will work.
 
Greetings everyone. After an almost month-long hiatus (much caused by getting a finger too close to a table saw blade) I'm back to attacking this bathroom.

Here is the drain/vent configuration for the shower. While I thought I could remove/reroute the HVAC duct which is in the way, the decision has been made to NOT use a pre-made shower base and make it, allowing us more flexibility in drain placement. We'll have to be careful to ensure proper drainage, but that's always the case.

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I guess if I could convert the old 4x10 duct to the newer round stuff I could then move the trap for shower drain to the other side of joist closer to center of drain.

Back to the other side of room are drains for toilet (on left) and vanity (right). I haven't yet cut the vertical 1.5" vent to add sanitary tee for sink drain as I want to get a long sweep 1.5 inch sanitary tee for that.

I was able to come up with two different configurations.

The first was the simplest, using a 3" 90 elbow with a 2" inlet on heel. I'm pretty certain it's not to code but thought I'd run it by you guys.

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It's hard to see here but that 3" 90 up to the toilet is a long sweep (or a least longer that the standard 90's)

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As I somehow knew that the above would not pass muster, I tried to use a big 3" long sweep sanitary tee that a former master plumber who now works at Lowe's recommended. It's not all that easy to get a or photograph, but hopefully you get the idea. The height of the main drain stack can be tweaked a bit if more slope is needed.

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I plan on replacing the copper inlet pipe to the toilet and can move it to make the toilet drain line up better, if needed. Though one question is should I consider CPVC instead? Most of the copper supply piping has pinhole leaks so it has to be replaced. I'm (obviously) not a pro, but have worked with copper enough so I'm pretty comfortable with it. So it's a question of durability. Just how long as CPVC been around? Will be the next "latest and greatest" new type of plumbing piping to end up deteriorating years after it is installed?
 
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I was wondering how things where going.
That wont be right
The waste line from the toilet can have that combo with another fixture tied in before the vent.
You were correct about the low heel outlet not flying either.
I'm headed out the door to work but i'll try to get back later.the horizontal line from toilet can be 3". the 2" you can turn down into the wall with a 90 and the connected to the stack with an up right wye.
you can use that low heel outlet 90 for the toilet change in direction from horizontal to vertical w/ the 2" lookin' up.. then a 2" santee on top of the 2" of the low heel oulet for the tub drain.

Quick sketch

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The waste line from the toilet can have that combo with another fixture tied in before the vent.

I had to read your post twice but the scary thing is I am sure you meant "can NOT have that combo" and think I understood the rest.
 
I tried the configuration in the sketch but was worried about trying to get the 2" from vanity/shower over the toilet drain.

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So switched things around a bit. I didn't have the correct double elbow to use where the shower and sink drains join and ran out of 2" PVC when taking that drain into the final wye under the toilet santee and tub drain. Or maybe a santee or double santee with cleanout plug in the center. Though I guess with that there is still the chance of a snake jumping over to other side. Prolly best to use long sweep 90, followed by long sweep santee for sink (new hole in joist?)..

Though... I could take the shower drain all the way down the wall and then come down the holes I drilled for the tub a long time ago when I started this debacle. Shower drain would join the sink right before it goes thru that charred hole.
 
Wow.
Made some notes on some photos. The one with ??? I'll presume is for a vanity sink. The santee I marked N/G will need to be reconfigured but that's minor.
I see you already installed the wye on the stack. Good.
Remove the long sweep tee for the tub drain. That needs to be a santee.
Like the 3 X 2 you had in there before.
The take that santee and turn it a little to the left. It will give you clearance for the shower/vanity drain.
Now for that p-trap & drain farthest from the toilet: Is that for a shower?
Shower drain should be 2". A bathtub only needs to be 1 -1/2"

Also take out that extra 90 on the toilet waste line to santee.

Oh yeah, That was supposed to be a " can't " sorry for the confusion.

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The combo does NOT ;) work well for a vent because the branch connects to low for the trap arm.
The Vent is to break the siphon on the trap and if it is lower than the bottom of the trap arm it fails.

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