Sink Vents

My sister lives in a townhome and is remodeling her kitchen. Her old sink was vented outside and the pipe ran through the soffit, which she would like to remove during the remodeling process. Her contractor mentioned to her the idea of installing a sink with a vent only under the new counter top. I've never heard of this venting procedure and wondered if anyone has experience with this method.

Thanks in advance for your help-

Greg Beck

These are called Air Admitance Vents (AAV). They are also referred to as Studor vents after the original name. They do work, but there are some areas that do not allow them and some plumbers are adamently against them. If you you do use one, it should be left accessable so it can be easily replaced should it fail. This whould not be difficult and the plumber would know how to do this. These can not totally replace a vent to the outside within the drain system.