jar546
Forum Coordinator
According to the 2018 International Plumbing Code, Section 709.3 "Size of Fixture Drains", the minimum size of a trap arm for a bathtub is 1-1/2 inches in diameter. Is this correct?
Wasn't the question about a trap arm?How about this too?
407.2 Bathtub Waste Outlets and Overflows
Bathtubs shall be equipped with a waste outlet that is not less than 11/2 inches (38 mm) in diameter. The waste outlet shall be equipped with a watertight stopper. Where an overflow is installed, the overflow shall be not less than 11/2 inches (38 mm) in diameter.
Are you trying to put a trick question out here or what?2018 International Plumbing Code, Section 709.3 "Size of Fixture Drains"
FIXTURE TYPE | DRAINAGE FIXTURE UNIT VALUE AS LOAD FACTORS | MINIMUM SIZE OF TRAP (inches) |
Bathtub ^b (with or without overhead shower or whirlpool attachments) | 2 | 1-1/2 |
Nope. Trying to create accurate content. Having more than one person who chooses the same answer gives it more clout. Maybe I am wrong and looked too fast.....Are you trying to put a trick question out here or what?
PLUMBING APPLIANCES, APPURTENANCES, OR FIXTURES | MINIMUM SIZE TRAP AND TRAP ARM ^7 (inches) | PRIVATE | PUBLIC | ASSEMBLY ^8 |
Bathtub or Combination Bath/Shower | 1-1/2 | 2.0 | 2.0 | -- |
Under the UPC, the tub trap arm may be 1-1/2", but once the vent comes off, any horizontal drain carrying the tub has to be at least 2". A 1-1/2" drain is good for 2 DFU vertically (with some limitations) but only 1 DFU horizontally, and a tub is 2 DFU.And for those who follow the UPC...
I was just indicating that ALL signs point to 1.5"......Wasn't the question about a trap arm?