island vent

Larry4

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
 
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.
 
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.
 
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.
 
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.
 
larrygman said:
. 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
Click to expand...


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.
 
The best way to vent an Island sink is as pictured.

islandvent.jpg

Nice picture of an Island Vent, Washington State UPC code
Click to expand...
 
Last edited by a moderator:
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.
 
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.
 
SewerRatz said:
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.
Click to expand...

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.
 
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.
 
You must log in or register to reply here.

Similar threads

S
Can this be a dry vent for a lower level bathroom?
Replies
0
Views
201
superboer08
S
C
Water Closet DWV Design - Straight Vertical 4" Drain - Lifted Hous
Replies
12
Views
536
Jeff H Young
Jeff H Young
justinalanbuckley
Advice for DIY install of drain pump for kitchen sink/dishwasher.
Replies
0
Views
265
justinalanbuckley
justinalanbuckley
M
Three questions about Bathroom DWV plumbing...
Replies
8
Views
18K
MG70
M
T
Fixing PO’s DIY Masterpiece - Bathroom Remodel Venting and Trap Questions
Replies
1
Views
509
T_N
T
Back
Top