Welcome to Lowe's
Find a Store

Prices, promotions, styles, and availability may vary. Our local stores do not honor online pricing. Prices and availability of products and services are subject to change without notice. Errors will be corrected where discovered, and Lowe's reserves the right to revoke any stated offer and to correct any errors, inaccuracies or omissions including after an order has been submitted.

Unclog the Main Household Drain

A clog in your plumbing often affects a single sink, tub, shower or toilet, but if more than one fixture is backed up, you may need to clean out the main drain line.

How to Unclog the Main Household Drain.

Tools & Materials

Product costs, availability and item numbers may vary online or by market.

Missing anything? Shop Online

Clearing the Clog

Augers — also known as plumbing snakes — and sewer rods are effective against some clogs in the main drain line.

Caution

If you suspect a blockage in the main drain line, don't use the plumbing system in your home until it's cleared. Getting more water into the line could cause waste water backups in the home.

Step 1

Drain Line Cleanout.

Find a clean-out plug located on a large drain pipe in areas such as your basement, crawl space, garage or near the foundation of your house. Remove the plug with an adjustable wrench. Waste water may drain out when you open the cleanout and when you break the clog. Stand clear as you remove the plug and as you work on the clog. If the drain line is vertical, place a bucket under the clean-out.

Caution

Wear the appropriate safety gear and follow the manufacturer's instructions for use and safety when using any drain-opening product. Use caution when clearing clogs in older pipes. Some products may not be suitable. If you have older or corroded pipes, you're concerned about damage, or you can't clear a clog, contact a professional plumber.

Step 2

  • When using an auger, push in the cable until it reaches the obstruction. Turn the handle clockwise to dig the tip into the clog. Twist, push and pull the cable to break it up.
  • When using a sewer rod, direct the rod through the pipe until you reach the obstruction. Push the rod forward and pull it back to break up the clog.
  • Work the auger or rod in both directions of the drain line — back towards the house and out from the house.
Good to Know

Standard, hand-powered drain-clearing tools aren't effective against a clog caused by tree roots that have entered an underground pipe. Contact a professional plumber to clear this type of blockage.

Tips to Prevent Drain Problems

  • Don't empty into a sink any coffee grounds, grease or material that can clump or solidify.
  • When using a disposal, run plenty of cold water to flush food particles down the pipe.
  • Clean strainers and pop-up stoppers frequently.
  • Don't flush heavy paper products down the toilet.
  • Consider using a drain maintenance treatment, designed to reduce buildup in pipes. Make sure it's suitable for your system.
  • If you have a septic tank, have a professional inspect it every two to three years, or as required in your area.

Watch our DIY Basics video: How Do I Unclog My Toilet?