Moving a toilet, need to plumb it

[Zelbrew]

I want to move a toilet into what has been a closet, and it is way far from the existing location. A few things to figure out:

1. The new location sits nearly directly over the main waste line not far from where it exits the crawlspace through the wall. Is it as simple as dropping down an into the main line with a sweep 90? If so, should I plan on the new fitting into the main line to be vertical, or can it be plumbed in at an angle.

2. I was planning on removing drywall to put in the vent and adding some insulation for sound dampening. There is a sink on the same wall about six feet away, so I figured it would be easy to tie into the vent system up in the attic. But, anything to think about here?

3. The new toilet hole will be almost smack dab over a joist that runs parallel with the toilet wall. I have looked into notching, and I think I can get away with that in concert with an offset flange, as it is close to the end of the joist where it is supported. It only buys 1.5 inch, so I'll probably still have to bump away from the wall and live with a bit of a gap. Otherwise, I'd have to look at 10" or 14" rough-in toilets.

4. I was hoping to go ahead and move the toilet and try it in this location awhile to prove the concept before we overhaul the bathroom. However, there is not tile there and if I install it now, the flange will be too low after we do tile (and possibly more subfloor). Is there a way to install a flange now and then raise it later, or should I just plan on having to cut the flange off later to bring it higher.

The corner at the end of the concrete wall is the new location; the toilet will be basically on the concrete wall (above the floor obviously). The pipe that the currently toilet plumbing ties into is perpendicular to the main waste line outside the right frame of the current pic; the toilet is about 15 to the right.

 

[Terry]

No plumber likes an offset flange. They don't flush well.
Going with the 10" would be the easiest and least expensive, and then the 14" after that, though those do cost more.
A closet flange can be raised at installation. They make spacers for that.

Venting within six feet for a toilet is pretty normal. A bathroom lav is sometimes used as a "wet" vent, run in 2"

 

[Sponsor]

 

[Zelbrew]

I thought I had read on here that as long you you used the "good" offsets, it would be OK.

It looks to me if I use a 10" it will still need to be hitting the joist. It might clear with a 10" and an offset after the subfloor and tile, but it might still need some notching.

Regarding the raising of the flange: If I install now without the eventual height of the finished floor in place, the flange will be permanently fixed, right? So later after tiling and all and I need to raise it, I'll need to cut it out and add height to the riser, right? Unless there is some other solution.

 

[Terry]

The engineers on this site talk up the offset flanges.
The plumbers, working with toilets and plumbing all of the time, hate them. But what do we know, it's just what we do for a living.

In the Seattle area, the plumbers install the closet flange on the plywood, the flooring guy cuts around the flange, and then at installation, either we stack two wax rings, or use a deep wax ring. I've been doing this for 50 years, and it's perfect. Has been, and always will be.

 

[Jeff H Young]

I avoid offset flanges , I was taught they are illegal and respected that. There is a 45 flange I don't know if its considered an offset but I would expect they are ok never used it.
Too little time here to be worried about Vinyl or some thick tile . All my flanges go down on the wood as well.

 

[Terry]

Can you sister a floor joist alongside the other one?

 

[Zelbrew]

I could sister, but obviously the less cutting of joists, better. I wonder how much notching the offset saves over the 45. If the notch has to go deeper than allowable, I could sister to retain strength of the notched joist, but only if I can position it over some. Like I said, it is at the end of the joist, so that is best case.

So, how about the plumbing stuff? Anything preventing me from just dropping straight into that main waste line. If I use a 45 flange on the outside of that joist, it will be going in that direction already. If I go on the inside of the joist, I'll have to do some zigging.

 

[Zelbrew]

Here is the view from the top. It is kind of hard to see the pencil notations, but you can see the approximate location of the joist, and the 12" mark is slightly offset toward the wall, next to that hole. I have two offset flanges because I was comparing two brands. Also, there is a 10" mark. Maybe I could squeeze a 10" rough-in in there without notching the joist, but how much fudge room do they have built in?

One other thing I was considering was adding another layer of drywall on that wall to increase sound dampening (the living room is on the other side), which would push the 12" toward the the front edge of the joist, which might make a 14" rough-in possible without notching, but I am already cutting it close on clearance from the front of the toilet to the swing path of the door. Plus, like you said, Terry, the 14" ones are more expensive.

 

[John Gayewski]

I'm not sure what concept you want to "prove". That the piping will fit? Or the toilet will flush?

 

[Zelbrew]

Ha. That we like the location. It will be going into what is currently a closet that is next to the vanity and shares a wall with the living room. The other thing is that moving the toilet now will allow us to finish making the other end of the bathroom a closet. It is kind of a weird configuration now, hard to explain. I am less worried about the height of the flange. I can either stack wax rings or re-do the flange when the subfloor/tile gets done eventually.

 

[Jeff H Young]

I'd put the toilet where I wanted and use the full 45 style flange (never used one but Id fully trust it I'm wondering if Terry or anyone has first hand knowledge on performance) and deal with the structure it looks like you have a girder close by. I can't get good understanding from Post #1 what your doing perpendicular to this , and corner of concrete just really losing me on your details my guess is the toilet is going to hit the second joist to the right from the concrete in picture

 

[John Gayewski]

I've used an offset flange. I haven't noticed a difference but we do avoid them as they aren't legal. I don't really spend a lot of time with toilets after I plumb them so I can't really say for sure, but they function fine during testing.

 

[Zelbrew]

OK, sorry. If you look down the concrete wall on the left, the toilet will be positioned on the wall that sits above the concrete wall, nearly all the way to the corner. The joist in question (which you can't really see in the pic) is parallel to the concrete wall on the left. It is the first joist from the concrete wall, and 12 inches is right on the joist as measured from the drywall upstairs. That beam in the foreground of the pic is what the joists are attached to. The pvc that running away from the camera is the main waste line--it exits the crawlspace through that wall in the background of the pic, which is the foundation.

In the other pic, I have penciled the location of the joist; the wall is at the top of the pic.

 

[Jeff H Young]

I've used an offset flange. I haven't noticed a difference but we do avoid them as they aren't legal. I don't really spend a lot of time with toilets after I plumb them so I can't really say for sure, but they function fine during testing.

Hey John did you ever use the "offset " like in the Pic of ABS? the one that is essentially a full 45 fitting I would expect legal.
I've put dozens or many dozens back in my Tract home days its kind of shameful but working for some companies you gotta do whatever sometimes. mainly on slab floors where for whatever reason the measurement is off

 

[wwhitney]

I avoid offset flanges , I was taught they are illegal and respected that.

You and John both mentioned that, and IIRC you are both in UPC jurisdictions. I looked at the 2018 UPC (2019 California PC), and I'm not seeing anything. [Also, the OP in Indiana is subject to the 2006 IPC, so this is not directly relevant to the OP.]

There is 402.6.3, the last sentence of which says "Offset, eccentric, or reducing floor flanges shall not be used." However, the title of 402.6.3 is "Securing Floor-Mounted, Back-Outlet Water Closet Bowls" and every other sentence in that section is explicitly about "floor-mounted, back-outlet" WCs. So I take it that last sentence means "shall not be used" for the wall flange of a back-outlet WC.

Am I missing something, or is the idea that offset flanges are illegal under the UPC just due to an out-of-context interpretation of that sentence in 402.6.3?

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Cheers, Wayne

 

[JCar915]

I have basic knowledge of plumbing and I created this account to ask questions so I wouldn't screw stuff up. So I wouldn't be able to help with that. What I can help with is cutting out a section of that joist. You absolutely will want to avoid it if possible but if you are set on it and don't want to use the offset flange then this is the way. You would have to cut out a section of the joist where you want to move the toilet. The joists on each side of the cut joist would have to be sistered (to the outside and the full length, load bearing to rim joist). At each cut end of the joist you would attach a double joist or header. The header would run parallel with the load bearing beam and perpendicular to your cut joist and would span in between the original joists to the left and right of the cut joist. You would attach cut sections of joist to the header with a joist hanger and approved nails or strong tie screws (9# 1.5", 9# 2.5"). Then you would attach the header into the original joists using double joist hanger. A ton of work to move a toilet. It is hard to tell from a picture but this sketch is what I gather from it. You can call your local building dept and talk with an inspector. Most of the time they would be willing to answer a few questions without doing a physical inspection. Especially if you say "you had a contractor come out and he told you this was the way to do it. You just wanted to be sure that it was ok." If the inspector doesn't know off hand, he may put you in contact with a structural engineer. They may approve less work depending on your local jurisdiction. Maybe just the headers without sistering joists. Either way I hope you can come up with a much easier solution.

- Josh

 

[Reach4]

You probably know that the horizontal flows joining should all be via wyes and combos.

Here is the view from the top. It is kind of hard to see the pencil notations, but you can see the approximate location of the joist, and the 12" mark is slightly offset toward the wall, next to that hole. I have two offset flanges because I was comparing two brands. Also, there is a 10" mark. Maybe I could squeeze a 10" rough-in in there without notching the joist, but how much fudge room do they have built in?

One other thing I was considering was adding another layer of drywall on that wall to increase sound dampening (the living room is on the other side), which would push the 12" toward the the front edge of the joist, which might make a 14" rough-in possible without notching, but I am already cutting it close on clearance from the front of the toilet to the swing path of the door. Plus, like you said, Terry, the 14" ones are more expensive.

Adding wall thickness would decrease the rough in distance. So I presume that you were talking about coming up on the other side of a joist.

Regarding offset flanges that you don't have to glue into place, consider the Sioux Chief 889-GPOM. You can pull it, and as long as the floor thickness has not been increased excessively, you can put it back. It would go into a 4 inch pipe-size as you would get with a spigot 4x3 closet bend.

The trimming place would not be the same for you.

The downside of a 4 inch riser, vs 3 inch, is that the center of the pipe would be a bit farther from the joist.

 

[John Gayewski]

You and John both mentioned that, and IIRC you are both in UPC jurisdictions. I looked at the 2018 UPC (2019 California PC), and I'm not seeing anything. [Also, the OP in Indiana is subject to the 2006 IPC, so this is not directly relevant to the OP.]

There is 402.6.3, the last sentence of which says "Offset, eccentric, or reducing floor flanges shall not be used." However, the title of 402.6.3 is "Securing Floor-Mounted, Back-Outlet Water Closet Bowls" and every other sentence in that section is explicitly about "floor-mounted, back-outlet" WCs. So I take it that last sentence means "shall not be used" for the wall flange of a back-outlet WC.

Am I missing something, or is the idea that offset flanges are illegal under the UPC just due to an out-of-context interpretation of that sentence in 402.6.3?

Chapter 4 Plumbing Fixtures and Fixture Fittings: Plumbing Fixtures and Fixture Fittings, California Plumbing Code 2019 | UpCodes

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Cheers, Wayne

The reason I've always thought was the diameter doesn't stay the same. As a 3" ball won't pass through it. I can't say the code actually states that as a standard "a 3" ball shall pass" just that the diameter can't change. I believe the last time I looked there is an oval portion in these fittings that did get smaller than 3" while the inlet and outlet are 3". Not sure if that counts as a diameter change as one dimension is 3" but the other direction it does get smaller.

Let me ask this. What is the diameter of an oval?

 

[Reach4]

You could refer to the major diameter of an ellipse, and the minor diameter. https://www.storyofmathematics.com/area-of-an-ellipse/

If the (major diameter of an ellipse times the minor diameter) is equal to the ((diameter of a circle) squared), the areas are equal

I suspect a Sioux Chief offset 4 inch flange would pass a 3 inch ball, and I know that a 3 inch inside closet flange would not pass a 3 inch ball.

 

[wwhitney]

The reason I've always thought was the diameter doesn't stay the same. As a 3" ball won't pass through it.

Ah, for the UPC the applicable section would I believe be 310.5, excerpted below. Whether an offset flange complies with it is a great question.

Thanks,
Wayne

Chapter 3 General Regulations: General Regulations, California Plumbing Code 2019 | UpCodes

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310.5 Obstruction of Flow

No fitting, fixture and piping connection, appliance, device, or method of installation that obstructs or retards the flow of water, wastes, sewage, or air in the drainage or venting systems, in an amount exceeding the normal frictional resistance to flow, shall be used unless it is indicated as acceptable in this code or is approved in accordance with Section 301.2 of this code. The enlargement of a 3 inch (80 mm) closet bend or stub to 4 inches (100 mm) shall not be considered an obstruction.