Core TradesQuestion 91 of 700
An island sink uses a special loop vent because there is no adjacent wall to run a conventional vent up through. This island (loop) vent works by:
a.Rising as high as possible under the countertop, then returning down and connecting to the drainage or vent system
b.Discharging directly to the floor drain
c.Venting through the dishwasher
d.Connecting the trap directly to the water supply
Explanation
An island loop vent rises to the underside of the counter, loops over as high as practical, then drops and ties into the vent or drain, providing venting without a nearby wall. It does not discharge to a floor drain, vent through appliances, or connect to the supply.
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