Tools and Materials
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Key Takeaways
Replacing a toilet is a manageable DIY project that can be completed in a few steps.
Instructions
Step 1: Measure for a new toilet
Step 2: Remove the old toilet
Step 3: Prep the base
Step 4: Install a new seal
Step 5: Set the new toilet
Step 6: Attach the tank and toilet seat
Step 7: Test for leaks
Measuring For a New Toilet
Learning how to remove and install a new toilet starts with knowing how to size the fixture.
Determine the Rough-in Size
Step 1: Toilets are listed by rough-in size. To determine the rough-in size you need, measure from your back wall to the center of one of the closet bolts that secure the existing toilet to the floor. Measure from the wall and not from the baseboard. A rough-in size of 12 inches is the most common, but you may see 8-inch or 14-inch rough-in measurements as well.
Step 2: Measure any nearby water supply lines on the floor. Some toilets have a wider base that might not fit next to a supply line. It’s also a good idea to measure from the bowl to a sidewall to be sure that the toilet will fit in your space.
Step 3: If you have shelves or a cabinet above your toilet, you’ll also need to consider the tank height. To determine your existing toilet tank height, measure from the floor to the top of the tank lid.
Measure the Toilet Seat
Usually, toilet bowls are elongated for comfort, but if you have a smaller space you might need a round bowl. The shape will determine the toilet seat size. While toilet seats are generally standard sizes, it’s a good idea to have measurements when shopping in case there are some variations by manufacturer. Here’s how to measure toilet seat fit by collecting measurements from the toilet bowl.
Step 1: Remove the seat and measure from the center space between the seat bolt holes to the front edge of the bowl. Round bowls should measure 16-1/2 inches, while elongated bowls should be about 18-1/2 inches.
Step 2: Measure the distance between the center points of the bolt holes. This distance should be 5-1/2 inches.
Step 3: Measure the distance between the outer edges of the bowl at the widest point. This will usually measure between 14 and 14-1/2 inches.
Removing the Old Toilet
Once you have the new toilet, you'll need to know how to remove and replace a toilet. Key steps include turning off the water, draining the tank, popping off the toilet bolt caps to unbolt the toilet and lifting the toilet up and away from the toilet seal or wax ring.
Step 1: Remove the Water
First, use a utility knife to score around the base of the toilet. Most toilets have some caulking or sealant right around the bottom.
Next, you'll need to turn off the water. The valve is located on the back side of your toilet. Simply turn it to shut the water off. Then flush the toilet to get all the water out of the bowl and most of the water out of the tank. If there's any extra water in the tank, use a sponge to soak it up and squeeze it into a bucket.
Step 2: Remove the Tank
Once the water is drained, unscrew the water line connected to the shutoff valve. It’s a good idea to place a rag underneath to catch any remaining water.
Next, pop off the caps at the base of the toilet. These cover the bolts that secure the toilet to the floor, known as closet bolts. Use a crescent wrench to remove the nuts from these bolts.
At this point, if you have help, you can lift the toilet out in one piece. If you're working alone, it's easier to separate it into two parts. To do that, loosen the bolts underneath the tank and remove the tank first.
Put on gloves for safety, then lift the tank straight up and move it aside.
Step 3: Uninstall the Bowl
Use a water solidifier to keep any remaining water from sloshing out of the bowl. You could also use a sponge to get the water out. Remove the toilet bolt caps. Loosen and remove the nuts that hold the toilet bowl to the floor. Lift the bowl and set it out of the way on a garbage bag. Be sure to lift with your knees, not your back.
Toilets are heavy. You may find it easier to remove the tank from the bowl before uninstalling the bowl.
Step 4: Remove the Old Wax Ring
You’ll now see the exposed sewer line. To block odors and gases, place a rag into the opening.
Next, use a metal putty knife to scrape away the old caulk from the floor. Remove the old wax ring using a plastic putty knife and dispose of the residue.
Step 5: Add a New Wax Ring
Once everything is clean, it’s time to install the new wax ring. Check your manufacturer’s instructions.
Run the wax ring under warm water to soften it. You can handle the toilet wax ring install step in one of two ways.
- Set the new toilet bowl upside down on a towel and either gently press the ring onto the outlet under the bowl, or
- Place the toilet seal or wax ring on the flange in the floor.
For more on replacing a wax ring, our guide, How to Replace a Toilet Wax Ring, gives you step-by-step instructions.
Installing a New Toilet
How do you replace a toilet? The key steps are relatively simple and include placing new hardware and a new wax ring, securing the new bowl to the floor, attaching the tank and installing the seat. Here are the details for a typical project.
Step 1: Secure the Toilet Bowl
After placing the wax ring, lift the toilet base and carefully align it with the bolts on the floor. Lower it straight down and gently wiggle it to create a tight seal.
Step 2: Install the New Tank
Now install the new tank. Align the bolts on the tank with the holes on the toilet base. The tank will include rubber seals to prevent leaks.
Secure the tank using the provided washers and nuts. Start by hand tightening, then use a wrench for a snug fit. Be careful not to overtighten the nuts to avoid cracking the toilet. Make sure the tank is level.
Step 3: Reconnect the Water Line
Reconnect the water supply line and turn the water back on. Allow the tank to fill.
Check for leaks around the supply line and the gasket base. If it's leaking, tighten the bolts a little more. If it continues to leak, take the tank back off and be sure the gasket is seated correctly.
Step 4: Attach the Lid and Seat
Place the tank lid on. Use a screwdriver to attach the toilet seat.
Step 5: Test the Toilet
Now it’s time to test it. Flush the toilet a few times and check around the base. If there's a leak around the base and the nuts are tight on the closet bolts, the wax ring isn’t creating a tight seal. You’ll need to remove the toilet and install a new wax ring. Be sure to evenly set the toilet in place without tilting it to avoid damaging the ring.
If everything is working properly, finish by applying a bead of caulk around the base of the toilet.
Let's Get Started
Replacing a toilet is a relatively easy DIY project. You'll need to remove the old toilet, prepare the drain, install the new one and test for leaks.
If you prefer to leave this project to the professionals, Lowe's can do it for you.