island vent

Users who are viewing this thread

Larry4

New Member
Messages
24
Reaction score
0
Points
0
I will be plumbing in one island sink with a disposal attached. The island is only 6 feet horizonally from soil line below floor. If I oversize the drain below to 3" to the soil line will that act like a combo waste and vent. I was going to ask the inspector but didnt know if it was a total no no.

thanks ,

lar
 

Redwood

Master Plumber
Messages
7,335
Reaction score
13
Points
0
Location
Connecticut
I don't care much for oversizing the kitchen sink drain. With 3" there is a lack of scouring and when they clog they are a bear to get clean.
 

NHmaster

Master Plumber
Messages
3,176
Reaction score
5
Points
0
Location
S. Maine
I've never run into that. I have run a 3" right up into the base cabinet and connected there. I usually put a 3" wye and ECO under the floor but I can't remember ever having to clean it them out.
 

hj

Master Plumber
Messages
33,602
Reaction score
1,040
Points
113
Location
Cave Creek, Arizona
Website
www.terrylove.com
drain

Maybe you won't but someone will someday. Whether it is permitted or not depends on the local jusidiction. Sometimes they will let you run a 3" horizontal line and then tie both the drain and the vent into the top of it as a modified waste and vent.
 

NHmaster

Master Plumber
Messages
3,176
Reaction score
5
Points
0
Location
S. Maine
IPC will let you run it horizontal, come vertical through the cabinet base, 3" elbow with a 3 x 1 1/2 bushing. Miles better in my opinion than an island vent or a AEV.
 

Jimbo

Plumber
Messages
8,918
Reaction score
18
Points
0
Location
San Diego, CA
. If I oversize the drain below to 3" to the soil line will that act like a combo waste and vent. I was going to ask the inspector but didnt know if it was a total no no.

thanks ,

lar


Under CA code (UPC) combination waste/vent systems are ONLY for showers and floor drains. They are NOT allowed for sinks or other fixtures roughed in above the floor. 2007 CA Plumbing code, 910, and appendix B2.
 

SewerRatz

Illinois Licensed Plumber
Messages
1,681
Reaction score
10
Points
38
Location
Chicago, IL
Website
www.a-archer.net
The best way to vent an Island sink is as pictured.

islandvent.jpg

Nice picture of an Island Vent, Washington State UPC code
 
Last edited by a moderator:

NHmaster

Master Plumber
Messages
3,176
Reaction score
5
Points
0
Location
S. Maine
I dissagree. the loop vent is the most complicated, most likely to plug the vent and never get cleaned out and most complicated mess ever dreamed up. Much as I hate them, I'd use an AAV long before I would pipe that monstrosity ever again.
 

SewerRatz

Illinois Licensed Plumber
Messages
1,681
Reaction score
10
Points
38
Location
Chicago, IL
Website
www.a-archer.net
Sadly, the AAV,s are not allowed here in Illinois. The loop vent is the only option we have here. Properly installed I have never had any issues with them.
 

Redwood

Master Plumber
Messages
7,335
Reaction score
13
Points
0
Location
Connecticut
Sadly, the AAV,s are not allowed here in Illinois. The loop vent is the only option we have here. Properly installed I have never had any issues with them.

What is so sad about AAV's not being allowed there.
IMHO the place they belong is in the trailer park on the badly plumbed trailers.
 

hj

Master Plumber
Messages
33,602
Reaction score
1,040
Points
113
Location
Cave Creek, Arizona
Website
www.terrylove.com
vent

We called them "yoke" vents because they look like the device that is used to hold cattle. But that type of vent WILL let the sink drain until such time as the relief vent goes underwater. An AAV will stop draining as soon as ANYTHING blocks the connection to the main. An AAV therefore will give the impression of a blocked sink drain, when the real cause could be a blocked,or blocking, main sewer, leading to a misdiagnosis of where the problem is.
 
Top
Hey, wait a minute.

This is awkward, but...

It looks like you're using an ad blocker. We get it, but (1) terrylove.com can't live without ads, and (2) ad blockers can cause issues with videos and comments. If you'd like to support the site, please allow ads.

If any particular ad is your REASON for blocking ads, please let us know. We might be able to do something about it. Thanks.
I've Disabled AdBlock    No Thanks