Max length for a drain pipe w/o vent

Bcoleman6 · 02-26-2008, 09:32 PM

What is the max length a drain pipe can be from the main stack w/o needing its own vent?

Ron The Plumber · 02-26-2008, 10:01 PM

What size pipe are you talking about?

All lines need a vent.

Bcoleman6 · 02-26-2008, 10:14 PM

The drain pipe in question is 2" and runs four feet into the main stack which is of course vented. I also have the same type of run from a washer drain. Does this work as the vent or does it need to be vented directly after the P trap.

Ron The Plumber · 02-26-2008, 10:18 PM

You can run up to 5' on 2" according to my code before it has to connect to a vent, so 4' is good.

Bcoleman6 · 02-26-2008, 10:24 PM

Thank you Ron.

Knucklez · 02-26-2008, 10:49 PM

ho hum...

my kitchen sink does not have a vent at all.. and it's drain is 20' before it reaches the laundry sink drain in the basement (same drain) which also does not have a vent. then another 15' to the sewer drain..

no vent at all..

i hear "gurgle gurgle" whenever a sink drains.. and who to you if you try to use the wash machine at the same time that the kitchen sink is full of water for doing dishes by hand or something...

best i can tell, its been like this for 50+ years in this house. amazing.

so... as part of my upcoming "my projects" project.. i have a full kitchen reno.

..

starting with a ceiling vent for the kitchen

Knucklez

Ron The Plumber · 02-26-2008, 10:54 PM

Surprise your not sick all the time from sewer gases entering the house do to no vents.

Knucklez · 05-05-2008, 07:39 PM

aye, me too. but can't smell any exaust so whatever sewer gas there is must not be that bad.

i'm reading a lot of your posts ron on the subject for my kitchen reno project. really great advise. hopefully i'll get all my questions answered just by reading the threads and won't even have to post any new ones

Knucklez

majakdragon · 05-06-2008, 10:11 AM

Although I am aware that Code can change by area, I have not heard of a non-vented drainline, which also has a trap connected. Anytime water is discharged from another nearby drain, it causes a vacuum that can suck the water out of the trap and allow sewer gas to enter the home.

02-26-2008, 09:32 PM	#1
Bcoleman6 Member Join Date: Jan 2008 Posts: 95	Max length for a drain pipe w/o vent What is the max length a drain pipe can be from the main stack w/o needing its own vent?

02-26-2008, 10:01 PM	#2
Ron The Plumber Journeyman Plumber Join Date: Jun 2006 Location: Eugene, Oregon Posts: 1,994	Max length for a drain pipe w/o vent What size pipe are you talking about? All lines need a vent. __________________ Fix it right the first time, so you won't have to fix it a 2nd time. To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

02-26-2008, 10:14 PM	#3
Bcoleman6 Member Join Date: Jan 2008 Posts: 95	Max length for a drain pipe w/o vent The drain pipe in question is 2" and runs four feet into the main stack which is of course vented. I also have the same type of run from a washer drain. Does this work as the vent or does it need to be vented directly after the P trap.

02-26-2008, 10:18 PM	#4
Ron The Plumber Journeyman Plumber Join Date: Jun 2006 Location: Eugene, Oregon Posts: 1,994	Max length for a drain pipe w/o vent You can run up to 5' on 2" according to my code before it has to connect to a vent, so 4' is good. __________________ Fix it right the first time, so you won't have to fix it a 2nd time. To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

02-26-2008, 10:24 PM	#5
Bcoleman6 Member Join Date: Jan 2008 Posts: 95	Max length for a drain pipe w/o vent Thank you Ron.

Max length for a drain pipe w/o vent