Standard Kitchen Sink Drain Pipe Size

Some older sinks may have drains that connect to a 1 1 4 inch tailpiece but most modern drains have a 1 1 2 inch outlet.

Standard kitchen sink drain pipe size.

However most of the bathroom sinks use 1 inch drain pipe. It provides the right amount of flow to drain a kitchen sink during heavy use. The main sewer pipe leading to the septic tank or public sewer is usually 4 inches. The inlet must match the supply pipe and it can be a 1 2 inch female pipe thread fpt connector for galvanized pipes a 1 2 inch compression or sweat connector for.

A 2 inch sink strainer fits the standard bar sink drain. Drains connect to either a 1 1 4 inch or 1 1 2 inch tail pipe. This size is precisely the diameter of the pipe instead of the length. This pipe is the standard size for all kitchen sinks.

These drains like bathroom and kitchen drains use a p trap which is a j shaped pipe that connects to the main drain line. Sewer drains from laundry sinks or washing machines are 2 inches in diameter and those from sinks in the kitchen bathroom or powder room generally use a 1 5 inch pipe. Since all kitchens use this size of pipe it is best to stick with it during any repair. Every state may have different code on plumbing and it may affect the required size of the bathroom sink pipe.

A standard rule of thumb is that sewer pipes leading away from a toilet are 3 inches in diameter. When installing a new kitchen sink drain or repairing an old leaking one you need a particular size drainpipe.