How to Install a Toilet

If you’re replacing a toilet, you’ll first need to remove the old toilet. Here’s an overview on how to remove an existing toilet for replacement:

• Turn off the water at the shut-off valve located either on the wall or floor near the toilet.
• Flush the toilet to drain all the water from the tank and toilet bowl. Use a plunger to force any remaining water down the drain line. While wearing rubber gloves, remove any remaining water from the tank with a sponge and a bucket.
• Disconnect the supply line with an adjustable wrench. If the line has never been removed or has been connected for an extended period, it might be a little hard to loosen at one or both connection points. If that’s the case, use a heavy-duty lubricant to break down any corrosion.
• Have a bucket and rag on hand to catch and wipe up any water that leaks from the supply line.

If you’re working alone, it’s usually easier to separate the tank from the bowl. Lifting both pieces together can be difficult for one person.

• Remove the bolts that connect the bottom of the tank to the bowl with an adjustable wrench.
• Lift the tank straight up from the bowl and set it aside.
• Pop open the toilet bolt caps. Use a screwdriver if necessary.
• Use a pair of pliers or an adjustable wrench to remove the nuts and washers on the bolts that secure the bowl to the floor. If you find the nuts are rusted in place, use the heavy-duty lubricant to loosen the nuts. Then turn the screws to create as much space as you can at the base of the bolts. Use a hacksaw to cut the bolts off.
• If your toilet is caulked around the base, use a utility knife to score through the caulk seam.
• Gently rock the toilet bowl back and forth until you work it free and can lift it. Move it to the side to expose the old toilet seal.
• Remove the old toilet seal using a putty knife. Wipe away any excess with a damp rag or sponge.
• Stuff a rag into the open line in the floor to prevent sewer gases from venting into the home. Remove the rag before installing the new toilet.

Tip: To reduce water usaage, look for WaterSense labeled models when shopping for a new toilet.

Before answering “How do you install a toilet?”, it’s important to determine whether you need to replace the toilet flange.

The flange secures the toilet to the drainpipe in the floor and provides a connection point for the hardware found on the base of the toilet. The old toilet's flange and bolts can be reused when installing a new toilet if they’re in good condition. If it is cracked or broken, replace it with a matching flange.

Tip: If you're unsure of what type of replacement flange to buy, simply snap a photo of your old flange and use image search in The Home Depot Mobile App to find similar products.

You have two options for replacing the new toilet seal or wax ring:

• Rest the new toilet bowl on its side on a padded surface to protect the floor and the toilet and attach the replacement seal to the bottom of the bowl. The benefit to this technique is that you can be sure that the ring is in the proper position when placing the toilet over the flange.
• Alternatively, place the seal in position on the flange prior to lowering the bowl into place.

Tip: If thick tile has been added to your bathroom since the original toilet was installed, you may need a thicker toilet seal or wax ring.

Now that you’ve removed the old toilet and prepped the location, you’re ready to learn how to put in a toilet.

• Place the toilet bowl onto the flange, aligning the bolt holes in the base of the bowl with the bolts in the flange.
• If it helps, you can hold the bowl by the inside rim instead of the outer edges to get a better grip and more control as you lower it.
• Press down to set the seal.

Tip: Be very careful not to move or tilt the toilet after setting the toilet seal or wax ring on the flange, since you could break the seal and cause future leaks.

• Place a washer and nut on each toilet bowl bolt and tighten evenly the nuts onto the bolts.
• Alternate from one side of the toilet to the other as you tighten the nuts a little at a time. Be careful not to over-tighten the nuts and crack the porcelain bowl.
• If the bolts extend too far above the top of the washers and nuts, cut off the excess with a hacksaw.

Tip: Don't apply caulk around the base of a new toilet. In the event of a leak, the caulk will trap the water under the toilet and cause serious damage to your floor.

If you have a two-piece toilet, you'll need to attach the tank to the bowl. If you have a one-piece toilet, you can skip this step, since the bowl and tank are permanently attached.

• If not already attached, install the “tank to bowl” gasket onto the base of the flush valve. Insert the tank bolts and washers from inside the tank.
• Place the tank onto the bowl, aligning the shank of the bolts with the holes in the bowl. If the bolts extend too far over the washers and nuts, cut off the excess with a hacksaw.
• Secure the tank to the bowl by alternately tightening each tank bolt until the tank pulls down and meets the bowl.
• Reattach the supply line to the exposed portion of the fill valve sticking out of the bottom of the tank and to the supply valve coming out of the wall or floor.

The next step for how to install a toilet is choosing the toilet seat. Since there are many types of seats and lids, make sure to select a toilet seat that fits your toilet model.

• Elongated toilet seats are the most common seat type, since they're more comfortable. Round toilet seats may be more common in small homes and apartments where space is a concern.
• Find the correct toilet seat size by measuring your new toilet.
• A specialty item such as a raised or heated toilet seat may have special installation requirements.
• Position and attach the new seat according to the manufacturer’s installation instructions.

Your final step is to test for leaks now that the toilet is installed.

• Slowly turn on the water shut-off valve and allow the tank to fill.
• Flush the toilet and focus on the base of the toilet and the point at which the tank and bowl meet.

Tip: Add leak-detecting dye to make seeing leaks easier.