Gregg G
Member
We are building a new house. The layout for the kitchen has the sink and dishwasher
36" and 72" from a side wall. There is no wall in front of the counter with the sink and
dishwasher. After looking at other posts, it seems the "island sink vent" setup is discouraged.
It sounds like a conventional trap arm and vent is a better way to go. If I tie the two sinks
(double sink and air gap on right side of sink for dishwasher drain) together and put the
trap under the left sink, that will put the trap weir just about 42" from the side wall. Since
I don't want the trap arm to go through the middle of the adjacent cabinet, I would run the
drain straight back to the back edge of the sink and into a long 90, then over to the side
wall. All of this will make the trap arm about 4'6" or so.
I believe the maximum distance from trap weir to vent is only 42" for a 1-1/2 trap. But for
a 2" trap, the maximum distance is 60". Is there any reason I should not use a 2" trap for
the kitchen sink and run the trap arm to vent as I have outlined? Or would you suggest
using the "island sink vent" method? There won't be a disposal because the house is on
septic.
Thanks for your comments/assistance!
36" and 72" from a side wall. There is no wall in front of the counter with the sink and
dishwasher. After looking at other posts, it seems the "island sink vent" setup is discouraged.
It sounds like a conventional trap arm and vent is a better way to go. If I tie the two sinks
(double sink and air gap on right side of sink for dishwasher drain) together and put the
trap under the left sink, that will put the trap weir just about 42" from the side wall. Since
I don't want the trap arm to go through the middle of the adjacent cabinet, I would run the
drain straight back to the back edge of the sink and into a long 90, then over to the side
wall. All of this will make the trap arm about 4'6" or so.
I believe the maximum distance from trap weir to vent is only 42" for a 1-1/2 trap. But for
a 2" trap, the maximum distance is 60". Is there any reason I should not use a 2" trap for
the kitchen sink and run the trap arm to vent as I have outlined? Or would you suggest
using the "island sink vent" method? There won't be a disposal because the house is on
septic.
Thanks for your comments/assistance!