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Old 01-06-2010, 04:29 AM   #1
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Default Under sink vent


I was told that there is a type of vent I can put for a sink that is not properly vented. What kind of vents are there and are they complicated to install?



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Old 01-06-2010, 04:54 AM   #2
My drains are stopped up
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There is what has been termed an "island-vent", some jurisdictions won't let you do it.

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2. Don't believe everything you think
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Old 01-06-2010, 04:40 PM   #3
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CPC 2007

909.0 Special Venting for Island Fixtures.
Traps for island sinks and similar equipment shall be
roughed in above the floor and may be vented by
extending the vent as high as possible, but not less
than the drainboard height and then returning it
downward and connecting it to the horizontal sink
drain immediately downstream from the vertical
fixture drain. The return vent shall be connected to the
horizontal drain through a wye-branch fitting and
shall, in addition, be provided with a foot vent taken
off the vertical fixture vent by means of a wye branch
immediately below the floor and extending to the
nearest partition and then through the roof to the
open air, or may be connected to other vents at a point
not less than six (6) inches (152 mm) above the floodlevel
rim of the fixtures served. Drainage fittings shall
be used on all parts of the vent below the floor level,
and a minimum slope of one-quarter (1/4) inch per
foot (20.9 mm/m) back to the drain shall be
maintained. The return bend used under the
drainboard shall be a one (1) piece fitting or an
assembly of a forty-five (45) degree (0.79 rad), a ninety
(90) degree (1.6 rad), and a forty-five (45) degree (0.79
rad) elbow in the order named. Pipe sizing shall be as
elsewhere required in this code. The island sink drain,
upstream of the returned vent, shall serve no other
fixtures. An accessible cleanout shall be installed in
the vertical portion of the foot vent.
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Old 01-07-2010, 03:35 PM   #4
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You have heard about either an island vent or a Studor (name brand) vent which is actually an Air Admittance Valve. They are easily installed but not legal in all areas. Being a mechanical vent, they can go bad and must be installed where they can be changed, not inside a wall. You can go to the Studor website to see these.
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drain vent, undersink, vent

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