How to Replace a Toilet

There are plenty of adventurous homeowners who are willing to take on formidable projects around the house, but for many of them, replacing a toilet isn’t even on the radar screen. Somehow the combination of an imposing, bolted down ceramic fixture; a pressurized water line; and an open drain leading directly to a sewer is enough to turn off some pretty handy people.

But if you can get past the gamey parts, let me assure you that replacing a toilet isn’t that big a deal. Manufacturers have even made the hard part hooking up the supply line a lot easier than it used to be. So if you’re ready to list that old avocado-green throne on eBay and upgrade to a modern, water-saving commode, here’s how to do it.

In this article I’ll detail the installation of a close coupled toilet. But you also can use this advice to install any toilet, be it a one piece Kohler or a temperature-controlled Toto. If you’re installing a toilet in new construction, I urge you to reinforce the floor under the toilet.

Turn off the water and drain the toilet

The first order of business is to pull the old toilet. Turn off its water, and then flush the toilet a couple of times. You’re emptying the tank now to reduce the weight of the toilet. You’ll still have a bit of water in the bottom of the tank and the bowl. Don’t worry about it.

Next, disconnect the supply line to the tank. It’s a good idea to use a small bucket to catch any drips and to keep some rags handy for the occasional mop-up.

It’s now time to disconnect the toilet from the drain line and prepare the closet flange for the new toilet. At this point in the job, I put on a pair of latex gloves. You can get by without them. I just prefer the extra measure of hygiene that they offer.

Use the correct closet bolts

When it comes to plumbing, a cardinal rule is to use hardware that doesn’t corrode in wet locations. This hardware includes the closet bolts, the long, machine-thread bolts that fit into slots in the closet flange and anchor the toilet to the floor. But chances are good that the bolts included with the toilet are brass plated steel. Check them with a magnet. If they stick to it, don’t use them. Same goes for the washers and nuts.

Your local plumbing supply will have brass bolts, nuts, and washers (stainless steel is good, too). If you can find them, get the extra long, 3-in. by 5 ⁄16-in.-dia. closet bolts. Take the extra step of affixing the closet bolts to the flange. This will ensure that the closet bolts won’t spin when you bolt down the toilet.

Before installing a new toilet, inspect the tank and bowl. With toilet bowls, the main problems that you want to avoid are a deformed inlet (the opening between the bowl and the tank); a crooked foot, where the bowl meets the floor; or a deformed horn on the bottom of the bowl where it meets the closet flange.

For more photos and details on how to replace a toilet, click the View PDF button below.