I was going to use 1-1/2" drain pipe for sinks, tub/shower, utility sink, and washing machine drain that will all lead into the 4" drain. My question is should I use a larger diameter like 2" or will the 1-1/2" be just fine ?
IPC Plumbing Code
International Plumbing Code
Georgia's Construction Codes
Georgia State Minimum Standard Mechanical Code (International Mechanical Code with Georgia State Amendments)