Sewer Shark Plumbing

Written by Chris Deziel; Updated December 29, 2018

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Categorized under Plumbers and Plumbing Contractors. Current estimates show this company has an annual revenue of less than $500,000 and employs a staff.

  • 1 Install Two Toilet Drains
  • 2 Plumb a Waste Pipe for a Bathroom Sink
  • 3 Plumb a Toilet From Start to Pipe
  • 4 Vent a Bathroom Toilet

The rough-in for a toilet involves three different kinds of pipes. The water supply, usually formed from 1/2-inch copper pipe, terminates at a shut off valve under the tank. The waste line, which may be 3- or 4-inch PVC pipe, ties into the sewer via a vertical waste stack and connects to the toilet by means of a closet flange. In addition, the waste line must be vented by a 2-inch pipe that terminates outside. The configuration of these pipes depends on the location of the toilet relative to pre-existing plumbing and the construction of the house.

Waste and Vent Pipes

  1. Install a 4-inch vertical PVC pipe that extends from a point at least one foot above the toilet bowl to the sewer. This is the soil stack and it should tie into the sewer with long sweep wye, or 'Y'-shaped, fitting. Use a plastic wye if the sewer pipe is plastic, but if the sewer is cast iron, install a cast iron wye with a threaded inlet and screw on a PVC adapter. Glue the soil stack to the plastic wye or the adapter with PVC cement.

  2. Place the drain for the toilet at a location in the bathroom that will provide enough clearance for the toilet when it is installed; 12 inches from the back wall is suitable for most toilets.

  3. Cut a 3- or 4-inch diameter hole for the drain in the subfloor with a reciprocating saw. The size of the hole depends on what size waste pipe you plan to use. A 3-inch line provides better drainage, but if the distance to the soil stack is more than 6 feet, 4-inch pipe is required.

  4. Fit a closet flange of the appropriate diameter into the hole in the bathroom and screw it to the subfloor with a screwdriver. The flange holds the toilet to the floor and forms the connection between the toilet and the waste line. Glue a closet elbow to the flange pipe under the subfloor with PVC cement. The elbow should be pointed in the direction of the soil stack.

  5. Glue PVC pipe to the elbow and extend it to the soil stack, maintaining a downward slope toward the stack of 1/8 to 1/4 inch per foot. Cut into the stack and glue in a 4-inch sanitary tee with a 3- or 4-inch opening, depending on the size of the waste line. Glue the waste line to the tee.

  6. Reduce the size of the opening of the top of the soil stack to 2 inches with a reducing coupling. Glue 2-inch PVC pipe to the reducer and extend it through the roof. This pipe vents the toilet and should terminate 1 foot above the roof line.

Water Supply Pipes

  1. Choose an existing copper pipe that carries cold water near the toilet and shut off the water to that pipe. Cut into it with a pipe cutter and solder in a copper tee with a 1/2-inch outlet.

  2. Assemble a supply line for the toilet with 1/2-inch copper pipe and fittings. It should run from the tee to the wall behind the toilet and extend about 2 inches beyond the wall under the tank. Solder all the joints after you have assembled the supply line, and affix the line to a stud in the wall behind the toilet with a pipe clamp.

  3. Terminate the water supply line with a shut off valve. You can either solder the valve to the pipes, or install a valve with a compression fitting. Make sure the valve is closed before you turn the water back on.

  4. Things You Will Need

    • 4-inch PVC pipe

    • Wye fitting

    • PVC threaded adapter

    • PVC cement

    • Reciprocating saw

    • Closet flange

    • Screwdriver

    • Closet elbow

    • 3-inch PVC pipe

    • Sanitary tee

    • 4- by 2-inch plastic reducing coupling

    • 2-inch PVC pipe

    • Pipe cutter

    • Copper tee

    • Soldier front steam. 1/2-inch copper pipe and fittings

    • Soldering supplies

    • Pipe clamp

    • Shut off valve


    If you're connecting a new toilet to an existing stack, you only need to install the waste and supply lines. To do this, the toilet must be placed within 10 feet of the stack.

    A configuration in which the waste line connects directly to the sewer will require venting for the waste line. You may be able to tie the vent pipe to an existing one that already runs through the roof. Vent pipes must either slope upward away from the toilet or be horizontal.


    Toilet plumbing can be complex, especially when there are obstructions, and if you install the pipes incorrectly, your toilet won't work properly. Consult a licensed plumber whenever you aren't sure how to proceed.

    You must get a permit from your local building department before roughing-in a new toilet.

References (1)

About the Author

Sewer shark plumbing products

Chris Deziel has a bachelor's degree in physics and a master's degree in humanities. Besides having an abiding interest in popular science, Deziel has been active in the building and home design trades since 1975. As a landscape builder, he helped establish two gardening companies.

Kk plumbing and drain is now open full time again was down with a injury that took longer to heal sorry for any issues as to not advertising again till now we have now teamed up with sewer shark and we can do a lot more this summer which includes replace and install holding tanks and wells excavation big or small and new septic feilds and repair and can now do commercial and industrial drain cleaning and residential all lines and don't forget to ask about back water valve in.