Vessel Venting

After reading the threads on vessel sink venting, I have a question. The existing vent is 18" downstream. The vessel has no overflow and will use a grid drain. My concern is that the water wil drain very slowly due to the lack of an overflow and good venting My questions are:
1) Should I run a new vent line?
2) Where would I run this new vent line from?
Thanks for any input

vessel

The venting has nothing to do with the vessel sink's slow draining. It is caused by the lack of an overflow which prevents air trapped between the sink drain and the trap from easily escaping. Until that air works its way out somehow, the sink will not drain, or at least not very well.


Choosing a vessel sink drain.

every vessel sink i ever put in drains S L O W . the first one I put in didnt even drain all the way. poor design.... I made the center hole in the grid larger and it helped.

vessel

I use pull up pop up drains, (some have to be modified so it lifts higher).

I have this same problem,

I used a couple of travertine vessels that are non overflow and installed a couple od Danser grids with decorative mushrrom heads.. These sinks drain so slow it;s rediculous..... anything I can do...... what about a AAV (air acuator valve??) or something to ease the drain problem...

Jeff

Unless I'm way off, an AAV won't help. They only let air in. You need to let air out so the water can drain.

These drain better than any others that I've tried. And they come in a variety of finishes. This drain style is also available for lavies w/overflows (K-7710).
http://www.us.kohler.com/onlinecatalog/detail.jsp?item=5870202&section=2

lack of Overflow Hole

personally i have a hard time understanding why "vessel" sinks in particular are victims of slow draining.

Is it more because of not having an overflow? Would a non-vessel sink also drain slow, if it had not overflow?

An overflow hole helps get water down a bit into the drain at first since it gives an easy escape route for the air that gets displaced. Then gravity pushes a path through the rest of the air. Kitchen sinks don't have overflows either, and yet we don't hear about them not draining well.

Currently I have two bathroom sinks that are a lot like vessel sinks since they sit on a counter. They have overflow holes. They drain well.

In another thread, I have been trying to figure out how to run a waste assembly that bends right under the sik and projects itself over to the back wall; in studying options I came across a Tee configuration that you can see easily if you look for a waste drain assembly called continuous waste (end outlet). The Tee end lets air escape. BTW, I still haven't found any 1-1/4" fine-threaded chromed brass elbows that will do what I want.

Is it not related to the lack of an overflow hole? Is it true that many other sinks, non-vessel-like, may or may not drain well either? I don't know. In recent years there are now sinks available, that don't sit on top of a countertop, and that don't have overflow holes either.

david