Minimum Trap/Waste Outlet Sizes for Plumbing Fixtures

Q: What are the Minimum Trap/Waste Outlet Sizes for Plumbing Fixtures, the the NYC Building Code?

A: Refer to Table 16-6 for the Minimum Trap Sizes, as restated below:

Fixtures & Trap Sizes:
Bathtub (with or without overhead Shower 1 1/2"
Bidets 1 1/2"
Combination Sink and Wash (Laundry Tray) 2"
Dental Unit or Cuspidor 1 1/2"
Drinking Fountain 1 1/2"
Dishwasher, Commercial 2"
Dishwasher, Domestic 1 1/2"
Floor Drain 3"
Funnel Drain 1 1/2"
Kitchen Sink, Domestic 2"
Laboratory Cup Sink 1 1/2"
Laboratory Sink 2"
Lavatory, Common 1 1/2"
Lavatory, Barber, Beauty Parlor, or Surgeon's 1 1/2"
Lavatory, multiple type (was fountain or sink) 1 1/2"
Laundry Tray (1 or 2 compartments) 1 1/2"
Laundry Standpipe 2"
Shower, Stall 2"
Shower, Gang 3"
Sink (Surgeon's) 1 1/2"
Sink (flushing rim type, flush valve supplies) 3"
Sink (service type with Trap Standard) 3"
Sink, Commercial (Pot, Scullery or sim) 2"
Sterilizers 3"
Urinal (Pedestal) 3"
Urinal (Stall Type) 2"
Urinal (Wall Lip Type) 2"
Urinal (Women's) 3"
Water Closet (Waste Outlet) 3"

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It's the Law: Women need more toilets than men!

Q: What are the requirements for Women's Toilet Rooms in Places of Assembly? How many additional fixtures are required for Women?

A: See Local Law 57/2005 for full details. The Plumbing Fixture Count has been amended so that the requirement for the number of Womens's Toilets serving most Places of Assembly is generally twice that of Men.

The amended count is a change to Plumbing Fixture Table RS 16-5 (Minimum number of required Plumbing Fixtures).

Unisex Toilet Rooms may be used to satisfy the total number of required Plumbing Fixtures for Women.