Drain, Waste, Vent or commonly called DWV is a non-pressure pipe and is typically used for drainage (to drain water from bathrooms), waste (sewers, soak away), and vents (bathroom ventilation). Though these pipes are manufactured in various sizes, ranging from 1-1/4, 1-1/2, 2, 3, 4and 6 inch, DWV is manufactured in Imperial sizes only (unit of measure). With the DWV pipes, the compound used is non-pressurized. Recyclable material is also used when manufacturing this type of pipe.