Washer / Utility Sink Plumbing Help

[Zerocool749]

Hi all,

I'm trying to plan out the plumbing I will put in for a new utility sink and washer. Here is the diagram,


I have an existing 1 1/2" or 2" floor drain about 10 inches away from a concrete wall. I plan to line up the washer, dryer, and utility sink against this concrete wall. There is no plumbing vent pipe nearby at all. The only vent I can find in the house is the main stack about 25 feet from this area of the house.

Above is my crude drawing. I'm going off this video. Is there there other pictures that would help?

Questions

How does this piping diagram look?

Shouldn't the AAV be higher than the utility sink in case of blockage / back up? In the video I linked, it's lower than the sink. How do I make that happen?

If there is any drawings that I could use as a guide for my situation, that would be great! I had a hard time finding one that fit my situation with a floor drain. Thanks for any advice!

 

[wwhitney]

Your drawing technically violates the IPC, because it requires a 3" drain starting at the point where the standpipe drain meets the sink drain. The third sentence in 406.2. [Fixture drain means a drain serving only one fixture.]

https://up.codes/viewer/michigan/mi...4/fixtures-faucets-and-fixture-fittings#406.2

So if you want to comply with that, there's basically two options that don't require a 3" drain. You could just install the utility sink, and drain the clothes washer through it. Or, Michigan hasn't adopted the 2018 IPC yet per up.codes, but there is a new option that allows the laundry sink and the laundry standpipe to share a single trap on a 2" drain:

https://up.codes/viewer/michigan/mi...4/fixtures-faucets-and-fixture-fittings#406.2

Cheers, Wayne

P.S. If you want to raise the AAV, just add a pipe segment between the san-tee and the AAV. If the AAV is spigot end (outside diameter is the same as a pipe, goes directly into a fitting hub), just add a coupling; if the AAV has a hub, then you'd need a pipe segment anyway.

 

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[Zerocool749]

Hi Wayne,

Thank you for this! Currently, my washer drains directly into the utility sink. I could leave that as is and save the hassle of putting in a washer standpipe. Also, I think I have only have 1.5" pipes, which would also violate IPC, which requires 2" for the standpipe. I measured from the outside and it is about 2", so that must mean the inside diameter is 1.5".

With that information, I will remove the washer standpipe from my diagram. It's not worth it.

Do I still need a AAV for only a utility sink drain? Currently, there is no vent I can find anywhere near this part of the house, except the sump pump.

 

[wwhitney]

Schedule 40 1.5" plastic pipe will have an outer diameter (OD) of 1.9", and 2" plastic pipe will have an OD of 2-3/8".

Yes, every trap needs a vent to protect it from siphoning.

If you just need an AAV for one sink, then something like RectorSeal Magic Trap looks like a very easy way to install one. I haven't used it myself.

Cheers, Wayne

 

[Zerocool749]

Thanks! I'm learning lots here. Yes, this will be a single sink far from the main stack.

My current utility sink has no vent and uses a S trap instead of a P trap. I wonder if that's why it drains slowly. Well, thanks for advice, I feel good on this now.

 

[Zerocool749]

One last question, I should place the AAV above the sink and not below the sink, correct?

https://up.codes/viewer/michigan/mi-plumbing-code-2015/chapter/9/vents#918.4

Based on this, I want to place the vent 6" above the rim of the sink. Something like this, correct?

Is that correct? Thanks!

 

[Reach4]

Alternative if that is 2 inch into the floor:

http://media.iccsafe.org/news/icc-enews/2018v15n13/2018SC-IPC802.pdf describes a standpipe trap shared with a laundry tub. As I read it, the 2018 change was to allow it in apartments, and this was available for houses in earlier versions.

 

[wwhitney]

One last question, I should place the AAV above the sink and not below the sink, correct?

https://up.codes/viewer/michigan/mi-plumbing-code-2015/chapter/9/vents#918.4

I don't have an opinion. The code section you quoted only requires it to be 4" above the sink trap arm, since it is an individual AAV.

Cheers, Wayne

 

[Zerocool749]

Awesome, thanks both of you!

 

[Zerocool749]

This is what I'm going to do,

Basically, I'm recreating what's in this picture that matches my situation.

Thanks everyone for advice!

 

[wwhitney]

When you say "floor drain", do you mean drain pipe that goes into the floor, or a fixture with a grate and a trap? Because in the latter case, you have to remove the trap below the floor.

Cheers, Wayne

 

[Reach4]

To minimized the width, this may help:
https://terrylove.com/forums/index....-washer-standpipe-position.90807/#post-652786

 

[Zerocool749]

Drain pipe that goes into the floor. Sorry for using the wrong terminology! Here is a picture. All of this is going to get remove and replaced. That PVC pipe isn't even cemented into the floor drain. I can literally pull it out.

 

[wwhitney]

That PVC pipe isn't even cemented into the floor drain. I can literally pull it out.

Given that, it may in fact be a floor drain, and you should check for a trap.

Or maybe it's a cast iron hub, and the donut is the wrong size?

Cheers, Wayne

 

[Zerocool749]

Okay, I will check for a trap! I just have to look down that pipe and see if there is water pooling in a trap, correct? I will also pour some water, just to see if it sits in a trap.

Yeah, I don't know what it is, I was just going to cement that PVC pipe coming out.

 

[wwhitney]

Maybe you can determine the materials on the middle annular piece (rubber?), and on the outer ring (clay? cast iron? plastic?).

Cheers, Wayne

 

[Zerocool749]

Okay, there is no P trap. I believe both the inside and outside rings are made of PVC. As you can see, I can just pull that PVC pipe right out of the floor.

Here are two pictures to help,

 

[Reach4]

Is that outer ring 7 inches OD?

 

[Zerocool749]

No, the outside diameter of the outer ring is about 3 1/2" to 3 3/4".

 

[wwhitney]

I assume slab on grade? Then the outer ring is just a block out in the slab so the inner fitting isn't compressed by being embedded in shrinking concrete. And the inner ring is presumably a hub of a fitting. So if you clean it up well, you should be able to solvent cement in your new fittings.

Cheers, Wayne