Maximum length of kitchen drain line

[JeffreyWisc]

As long as a kitchen drain line slopes the appropriate amount per foot, is there a maximum distance it can be run to the main stack?

 

[Twowaxhack]

I don’t think so.

 

[JeffreyWisc]

Thanks Twowax, I have a plumber meeting me at the new house on the 29th, just trying to understand what I am going to ask him about without looking like a moron. We are moving a kitchen sink which used to make about a 16 foot straight shot to the stack, now it seems like it will have to go about 22-24 Ft with a turn depending on the route the plumber wants to take. The basement is open underneath, and it‘s just a gym and a small shop, so I don’t care all that much about where he runs the drain line, as long as he can do it properly with respect to distance and slope. If a pipe has to be in a weird place, it will be ok.

Thanks for answering. Happy Holidays!

 

[Twowaxhack]

Yeah, that’ll be fine. He should have no problem. Make sure he put a couple cleanouts in the line. He probably will anyway.

 

[Paid2LayPipe]

if TDL becomes an issue depending on the vent, he can always increase the pipe size

 

[Twowaxhack]

if TDL becomes an issue depending on the vent, he can always increase the pipe size

He’s talking about after the vent. I’m not aware of a length limit if you maintain 1/4” per ft drop after the vent.

 

[Paid2LayPipe]

He’s talking about after the vent. I’m not aware of a length limit if you maintain 1/4” per ft drop after the vent.

I assumed it was after the vent, but you never know... if that is the case, there is no maximum.
in WI anyway. im not an expert in IPC

 

[Paid2LayPipe]

Thanks Twowax, I have a plumber meeting me at the new house on the 29th, just trying to understand what I am going to ask him about without looking like a moron. We are moving a kitchen sink which used to make about a 16 foot straight shot to the stack, now it seems like it will have to go about 22-24 Ft with a turn depending on the route the plumber wants to take. The basement is open underneath, and it‘s just a gym and a small shop, so I don’t care all that much about where he runs the drain line, as long as he can do it properly with respect to distance and slope. If a pipe has to be in a weird place, it will be ok.

Thanks for answering. Happy Holidays!

Honestly, I wouldnt run that far on 2" PVC. he should up that to 3" IMO

 

[Twowaxhack]

Honestly, I wouldnt run that far on 2" PVC. he should up that to 3" IMO

3” wouldn’t do anything for you.

 

[Paid2LayPipe]

3” wouldn’t do anything for you.

3" would change the pitch, give him more head room in basement if needed. As well as increasing the cleanout probability

 

[Twowaxhack]

3" would change the pitch, give him more head room in basement if needed. As well as increasing the cleanout probability

Not really, we still run 3” at 1/4” per ft because of lower flow volumes.

Over 25’ at 1/4” per ft your only dropping 6.25” anyway.

25’ isn’t that far.

 

[Paid2LayPipe]

Ok, im not gonna get in a pissing match here... I said IMO. Cheers bud

 

[Twowaxhack]

Ok, im not gonna get in a pissing match here... I said IMO. Cheers bud

Yes, and I gave you my opinion. Merry Christmas.

Oversizing kitchen drains just lets a bunch of crap build up before it stops up. Then you have a 3” line full of grease and crap.

It does nothing for you unless your doing a combo waste and vent. It still builds a lot of crap up in the line because not enough water is used to scour the pipe walls.

 

[MicEd69]

Oversizing kitchen drains just lets a bunch of crap build up before it stops up. Then you have a 3” line full of grease and crap.

You took the words right out of my mouth.

Kitchen = garbage disposals.

Garbage disposals = people don't know how to use them. Or NOT use them to put it better.

 

[JeffreyWisc]

I'm not having a garbage disposal.

 

[dmmsr]

Honestly, I wouldnt run that far on 2" PVC. he should up that to 3" IMO

Bigger does not necessarily mean better. It could actually be worse. If the line does not have anything more on it to allow more volume flow through the it, it won't scour properly and not flush the pipe clean when running water.