Closet Bend to Connect 3” Main Line to 4” Soil Stack?

[Radio Flyer]

I’ve installed a new picture window directly in front of my main-line-to-soil-stack connection in the basement. Because of this, I’d like to cut the soil stack down as low as possible while also lowering the main line. I’ll then cover it with a bench or something.

Question: Can I replace the current wye & cleanout with a 3” x 4” closet bend, or would that be too tight of a bend? I could use a short-sweep 4x4 elbow with a reducer, but I’m assuming the closet bend with keep things just a bit lower. I want to get this right, since I only have one shot at it (without chipping concrete). Any other ideas?

Separately, the previous cleanout is 21 ft. upstream and the next is 27 ft. downstream (outside), so should I keep a cleanout at this connection? If so, could I just add a standard 3” cleanout on the horizontal line just downstream of the 3” long-sweep 90?

Thanks for any advice!

 

[Radio Flyer]

Here's another view. Again, thanks for any input on this.

 

[Sponsor]

 

[Reach4]

Cleanout would be nice. I don't know if it is required.

So the 3 inch will be like the current one on the wall, but lower. I think a 4x4x3 sanitary tee will be a shorter fitting that still has the top port for the cleanout.
You can use a plug with a recessed wrench place instead of the elevated square.

Your idea of using the 3x4 closet bend is innovative. Logically I think it woud be OK. I am not a pro.

 

[Terry]

Horizontal bends are long turns and 45's
From horizontal to vertical you can use a medium 90.

You do need a cleanout at the end of a run below grade.

 

[Radio Flyer]

Thank you both.

For a medium 90, that would require a 4 in. 90 elbow and then a reducer for the 3-in line coming in., I guess.

I hoped maybe the closet bend would keep things even lower to the ground, but maybe Reach4's idea of a sanitary tee is just as low and would provide the cleanout all in one fitting??

 

[John Gayewski]

Closet bends are only allowed on water closets. The fitting isn't legal anywhere else in drainage. Vent systems would be fine.

 

[wwhitney]

For a medium 90, that would require a 4 in. 90 elbow and then a reducer for the 3-in line coming in., I guess.

4" quarter bend: 1.75" hub height + 3.875" to center line + 2.75" center line to 3" cleanout tee edge = 8.375"

3x4 reducing closet bend used as 4x3 increasing quarter bend: 1.75" hub height + 3" to center line + 2.75" center line to cleanout-tee edge = 7.5"
(saves 7/8")

4x4x3 san-tee: 1.75" hub height + 4.75" run + 1.75" hub height + 1.125" fitting cleanout adapter = 9.375".
(but if you could find a flush cleanout adapter for a 3" cleanout in a 4" hub, you'd save most of the 1.125")

The last option is the only one that gives a 4" cleanout.

Cheers, Wayne

 

[wwhitney]

Closet bends are only allowed on water closets. The fitting isn't legal anywhere else in drainage. Vent systems would be fine.

The hub x spigot closet bends in Charlotte's catalog appear to have a sharp inside corner so obviously wouldn't be suitable. But the hub x hub reducing closet bend looks to have proper radius all around.

Cheers, Wayne

 

[Radio Flyer]

4" quarter bend: 1.75" hub height + 3.875" to center line + 2.75" center line to 3" cleanout tee edge = 8.375"

3x4 reducing closet bend used as 4x3 increasing quarter bend: 1.75" hub height + 3" to center line + 2.75" center line to cleanout-tee edge = 7.5"
(saves 7/8")

4x4x3 san-tee: 1.75" hub height + 4.75" run + 1.75" hub height + 1.125" fitting cleanout adapter = 9.375".
(but if you could find a flush cleanout adapter for a 3" cleanout in a 4" hub, you'd save most of the 1.125")

The last option is the only one that gives a 4" cleanout.

Cheers, Wayne

Wow, that was some quick calculating! Thanks! I'll take a look at the Charlotte catalog.

 

[John Gayewski]

310.3 from UPC is where I decided they aren't legal. I suppose it could be interpreted differently.

 

[wwhitney]

310.3 from UPC is where I decided they aren't legal. I suppose it could be interpreted differently.

Since the proposed use of the fitting is not as a closet bend, I don't see how that would be applicable.

A related question is whether it would be legal to take a 3" outside / 4" inside fit closet flange, cut off the appropriate part of it to make a 4" inside fit bushing, and then install a 3" street quarter bend into the 4" inside fit bushing into the 4" vertical pipe.

Cheers, Wayne

 

[John Gayewski]

Since the proposed use of the fitting is not as a closet bend, I don't see how that would be applicable.

A related question is whether it would be legal to take a 3" outside / 4" inside fit closet flange, cut off the appropriate part of it to make a 4" inside fit bushing, and then install a 3" street quarter bend into the 4" inside fit bushing into the 4" vertical pipe.

Cheers, Wayne

The use of a 3x4 closet bend is limited to use for a water closet. This would be how it's interpreted in my area. The fitting being called a closet bend is manufactured as such and for that purpose. Other uses could be legal or interpreted as such, just not in my experience.

 

[wwhitney]

Right, the question is whether a product marketed as a 3x4 hub x hub closet bend, which observably has the same curvature as a 3" quarter bend, may be used as a 4x3 increasing quarter bend.

How about using/fashioning a 4" inside pipe bushing to allow a 3" street quarter bend to join to a 4" pipe? Any issues with that?

If the 4x4x3 santee with 4" fitting cleanout adapter is not too tall, that is the simplest option.

Cheers, Wayne

 

[Radio Flyer]

Right, the question is whether a product marketed as a 3x4 hub x hub closet bend, which observably has the same curvature as a 3" quarter bend, may be used as a 4x3 increasing quarter bend.

How about using/fashioning a 4" inside pipe bushing to allow a 3" street quarter bend to join to a 4" pipe? Any issues with that?

If the 4x4x3 santee with 4" fitting cleanout adapter is not too tall, that is the simplest option.

Cheers, Wayne

I'm thinking I'll go with the 4x4x3 Santee you suggested as the simplest option. I found a 4-in flush cleanout adapter that will accept a 3-in flush cleanout plug, so the height will be only about an inch more than the closet bend.

I feel the closet bend COULD work, but the cleanout would be much harder to access, since I would want to face it toward the wall for space. (See photo) Using the santee, however, the cleanout will be directly above the soil stack.

Admittedly, I'll have a 3-in clean out for a 4-in pipe, but hopefully it will be workable.

 

[Reach4]

Admittedly, I'll have a 3-in clean out for a 4-in pipe, but hopefully it will be workable.

I am thinking something like https://www.walmart.com/ip/4-Hub-Fi...nk-Plug-PVC-PartNo-C60009-JonesStep/166931176

 

[Radio Flyer]

I am thinking something like https://www.walmart.com/ip/4-Hub-Fi...nk-Plug-PVC-PartNo-C60009-JonesStep/166931176

Hey, that looks perfect! Thanks!

For the horizontal line along the concrete wall, I hope to have the line touching the concrete so I can then fur out the wall just beyond the depth of the PVC fittings and install drywall. (Keeping the wall thin so it won't project beyond the side of the picture window.) I suppose this will involve plenty of tapcons to mount the lumber "studs" above and below the pipe and some kind of pipe straps.

 

[Reach4]

4" PVC Hub Fit Cleanout with 3-1/2" Countersunk Brass Plug

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would be another. I expect there are other similar choices.

 

[Radio Flyer]

So far, so good. Thanks again for all the help on this!