[vent_questions]

Hi,
Need some serious help please :)

I'm setting up a Dog Bathing Tub in the basement to wash dogs in. We already have a sink and cabinet in the basement from the previous home owner. Please keep in mind this is the basement although it looks like an upstairs kitchen. I guess the technical term is a "wet bar" in the basement. I was originally thinking I could just tap into and extend the existing drain in the picture below from the sink to the but, but after reading a bit online I think I exceed the maximum venting length for the drain. It's ABS piping @ 1 1/2"

The Dog Bathing Tub is located on the left of the picture with the tub faucet holes and tub drain hole on the right hand side of the tub. I'll install a P drain, but when I measure the distance from the drain to the vent stack it's close to 10' I will also be connecting the existing faucet to the drain. I have enough room to slope the drain 1/4" per foot, but now I'm concerned about the venting situation. Do I have to worry about this or will I be okay?

Are there any suggestions you have? Is there other ways to vent properly? I was thinking I could vent up though the side of the house but I'm not sure if that's allowed because there is a window above where the tub is located.

Will I have to move the tub to another location?

Any thoughts would be much appreciated. Thanks!

[vent_questions]

I forgot to mention the vent stack is located in the right corner wall just behind and to the right of the existing faucet/sink in the picture above. Thanks.

[hkstroud]

What makes you think it is not vented. You said vent stack is in the wall didn't you? Can't tell what kind of piping you are using but you do know you have an S trap rigged up don't you.

[vent_questions]

Hi Harold,
Thanks for the quick reply. The existing faucet is vented, and aside from it being an s trap, it works fine from what we've seen (been in the house for almost 1.5 years, although hardly use this faucet), but I guess my concern is once I extend the current sink faucet drain to the left so I can connect the tub drain into it as well am I not going over the maximum length that I can run a drain pipe? I read somewhere that for 1 1/2" pipe I can only have the drain pipe run 3-5 feet. Can I have it run the approx 9-10 feet it will take to connect it to the tub?

When I run the new plumbing I'll be changing the existing sink faucet set up. I've heard that s trap aren't that safe and it's better to have a p trap set up.

I'm still new to plumbing and I may be interchanging words, but I'm very eager to learn I hope I'm explaining the situation better now, and any feedback is really appreciated.

Thanks again for the quick reply!!

[hkstroud]

By tub I assume you mean the laundry tub at the end of the cabinets. You can have a drain as long as needed. What you must do is vent it within a specified distance of the trap. For 1 1/2 pipe I think it is 5'. Tom will correct me if I'm wrong. To vent the laundry tub you will either go into the wall and add a vent line above the top of the tub. Or, assuming they are approve in you area, install a AAV (Air Admittance Valve) after the trap.

[speedball1]

What you must do is vent it within a specified distance of the trap. For 1 1/2 pipe I think it is 5'

. In point of fact, with one exception, the distance between trap and vent's 3 1/2' for 1 1/2". and 5' for 2".

I think you picked the ideal spot for your "doggy tub". You're planing on teeing off form the sink drain to pick up the new tub, correct?
OK! I would run the new drain in 2", ( you're going to get a lot of doggy hair going down that drain) and 5' on down the line lay a sanitary tee on its back and install a AAV ( Air Admittance Vent). That would take care of the vent problem. I should have asked. Will this be permitted and inspected? Regards, Tom

[Widdershins]

The 1-1/2 pipe you see coming out of the wall is called the trap arm, and you cannot tie into it -- You are allowed only one trap on a trap arm.

I think your best bet would be to cut out the back of the cabinet and cut in a Sanitary Tee below the existing Sanitary tee, you can then turn it on a 45 and run through the adjacent cabinets to the wash up sink and install an AAV in the top of a Combination Wye just before you exit the last cabinet -- The AAV should be at least 6" above the trap, higher if you have the clearance.

[vent_questions]

Thanks hkstroud, speedball1, and Widdershins (hope I didn't miss anyone). I love all the feedback!

This is a horrible picture I did up but is this what you mean? I've never heard of AAV so will have to read up on it. I am planning on teeing off from the sink drain (I'll replace that whole piece so that I'm coming off new from the trap arm). So will I do the new drain line with 2" ABS and once I hit the exisiting trap arm reduce to 1 1/2" (which is the existing trap arm diameter)?

[vent_questions]

Here's the picture. Forgot to attach. Remember, I know little and I'm sure this diagram is wrong. But appreciate all the feedback :)

[massplumber2008]

Hi all:

Here's an idea I think all will like... or at least it seems like a nice compromise... ;)

Here, I would repipe all of this with a new ptrap at the old sink just like VENT QUESTIONS suggested he would do, but I would treat the old sink and the new sink as individual fixtures off a branch drain line and I would add an AAV and ptrap at both the sink and the tub... see image below.

The only real issue I see in this case is that the trap arm is going to have a short pattern 90 instead of the long pattern 90 we would all like to see there, but I think it will work fine and both fixtures could technically run at the same time and each would still have its own vent.

Anyway, just more for you to consider vent questions. If you want to discuss more... let us know.

MARK

[vent_questions]

Hey massplumber2008,
You're diagram is a lot better then mine :)

Question. Do I need the AAV beside the sink. My understanding is because it's close enough to the vent (about 2') that I wouldn't need it at that location, but that I would definitely need it with the doggie tub

Is the diagram above based on 1 1/2" or 2" ABS piping?

Thanks again :)

[massplumber2008]

VQ:

I guess the first thing we should do here is back up and ask you to answer Speedball's question that you missed...

Is this job planned to have a plumbing permit pulled and will it be inspected by a plumbing inspector?

As you can see we have offered a couple solutions... fact is that they are really all kind of "ILLEGAL" in terms of plumbing codes. Each answer resolves your problem in that it allows you too hook up your sink, but breaks a code or two in doing it.

What we are trying to do is stick as close to CODE as possible, but how far we go from code really depends on what you intend to do here or just how important it is to you to adhere to code...

Please let us know the answer on this and then we will finalize an answer... O.K.?

Thanks you...

MARK

[Widdershins]

Here we go again Growler,
This has been going on between you and I over the years. There's a reason I asked if a permit would be pulled you know.

I was still typing up my own answer when you posted yours, Tom, so I hadn't seen your answer yet.

VQ:

As you can see we have offered a couple solutions...fact is that they are really all kinda "ILLEGAL" in terms of plumbing codes. Each answer resolves your problem in that it allows you too hook up your sink, but breaks a code or two in doing it.

>raises hand<

Ummm.. .

My suggestion wasn't "ILLEGAL", Mark -- Although I did neglect to mention that if this is being done to code, he will need to install a hair trap.

[vent_questions]

Hey MassPlumber,
I wasn't planning on getting a permit. Are you still able to help?

Ideally, I'm looking for a solution that is either to code or as close to code as possible. My main concern is creating a safe environment that doesn't produce any gases in the room and that vents properly.

Thanks again for all the feedback. Hope to hear from you soon...

[massplumber2008]

Widdershins...

If AAVS aren't allowed in VQ's area, or that pipe in the wall isn't 2" (how many fixture units is a doggie sink equal too anyway?) then your answer is as "illegal" as the rest... ;)

VQ:

A perfect job would have you cut into the 2" (or larger) waste stack in the wall much like widdershin's answer suggested and you would then run a 2" pipe over to the doggie sink. If plumbing code allowed it in your area, you would then install the AAV mentioned here as the vent. If the AAVs are not allowed in your area (what plumbing code do you fall under?) then you would need to take an individual vent and run it back to the wall and connect it into the VENT STACK at about 42" off the finish floor (well above the sinks)... that would be plumbing according to code. As you can see...quite involved.

If you don't want to open the wall and you want to use the AAVs then a less invasive answer is to pipe this up the way I drew it out above. Here, as I drew it, when the doggie sink drains it cannot siphon the ptrap from the kitchen sink because you provided an AAV (vent) for the sink. The vent in the wall will not vent the kitchen sink or protect the sink trap from siphoning when the doggie sink water flows by... no matter how close. Heck, the vent to the old sink never vented the old sink anyway... not with that s-trap in place.

Finally, you can increase the pipe to 2" if you want to, but if you install a full size dandy cleanout or a HAIR TRAP as posted by widdershin, then you probably don't need, too!

Let us know if you want to discuss more... glad too.

MARK

[Widdershins]

Widdershins...

If AAVS aren't allowed in VQ's area, or that pipe in the wall isn't 2" (how many fixture units is a doggie sink equal too anyway?) then your answer is as "illegal" as the rest...;)

It's pretty rare to find a place in this country where AAV's aren't accepted since the 2009 editions of all three of the major Plumbing Codes have come out, especially since the existing drain is vented and therefore meets the relief vent criteria required by some of the stricter jurisdictions.

As for the fixture unit count of the doggie sink, it has a 1-1/2" tail piece, so it would be considered a 2 unit Special Purpose sink in a residential application, or a 3 unit Special Purpose sink if the application were commercial.

The application appears to be residential so add the bar sink, which is 1 fixture unit, to the 2 fixture units and you're 1 over for an 1-1/2" drain -- As tough as my inspectors are, they aren't going to quibble over a single fixture unit on a retrofit.

[vent_questions]

Thanks hkstroud , speedball1 , Widdershins and massplumber2008!!

I really appreciated all your help. I'm new to this site so not really sure how to post comments or rate your answers, but wanted to thank each of you for your help.

Have a great day!