Toilet Drain Pipe Size

The top side of the flange which connects to the toilet is 4 inches in diameter while the bottom diameter of the pipe is 3 inches.

Toilet drain pipe size. Regardless of your plumbing code the minimum drain size for a toilet is 3 inches. The diameter of the waste outlet for the toilet may not match the diameter of the drain pipe the toilet may be 4. A standard rule of thumb is that sewer pipes leading away from a toilet are 3 inches in diameter. Some homes may use a 3 inch stack.

The bottom is designed to fit on 3 inch schedule 40 pipe used in most homes as standard sized drain pipe. The drain pipe connects to the flange which mounts the toilet itself and this flange is usually built to connect to 3 inch schedule 40. The drain pipe in your toilet carries waste away into the home s 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.

For instance the minimum pipe diameter for a washing machine drain is pipe with a 1 1 2 inch diameter. The toilet flange is the fitting that attaches the toilet to the drain line. Slope this pipe at 1 8 inch per foot grade to the main drain stack. The main sewer pipe leading to the septic tank or public sewer is usually 4 inches.

This is also the size of the closet bend pipe in most cases. The last size is 4 inch drain pipe that can be connected to 160 units in horizontal stack and 240 units in vertical stack. Water closet s flushing 1 6 gallons or less are rated at 3 dfus drainage fixture units. Compare the fixture to the minimum sizes of drainage pipe by fixture table.

Main toilet drain or stack 4 inch pvc or iron pipe. The standard size for a toilet drain pipe is 3 inches in diameter but drains up to 4 inches in diameter are often used. Some older model toilets flushing over 1 6 gallons per flush are rated at 4 dfus. Most homes use a 4 inch drain pipe only high rises supporting more than 5oo appliances use a larger pipe size.

The fourth size is 3 inch drain pipe that can be connected to 20 units in horizontal stack and 30 units in vertical stack.