Trade Secrets for a Professional Toilet Installation
What to Do Before Choosing Your New Toilet
Measure from the back wall behind your toilet to the toilet bolt. The toilet bolt is the bolt that sticks up from the floor through the porcelain on the foot of the toilet, usually covered by a cap. The job of the toilet bolt is to help create a watertight seal between the toilet bowl and the toilet flange and to secure the toilet to the floor.
There are three possible measurement distances you can get from the wall to the toilet bolt: 10 inches, 12 inches or 14 inches. The most common is 12 inches. In plumbing terminology, this is called a 12-inch rough. Sometimes these measurements are not exact. For instance, if your measurement is 11.5 inches, that would be a 12-inch rough. If you purchase your toilet online or from your local store, your rough measurement becomes very important.
Measure the length of your current supply tube. This way you will know what approximate length you require for your new supply tube. Never reuse the old supply tube. Generally, the distance between the outlet of the stop/shutoff valve to the water inlet of your old tank will be very close to the new toilet supply tube measurement. Hint; buy more than you need, you can always return it later. This will prevent you from taking several trips to the supply store. For instance, if you measured approximately 9 inches for your supply tube, then purchase a 9”, 12” and 16” supply tube and return the ones you don’t use.
Steel mesh toilet supply (also known as toilet connector) tube lengths are as follows: 6”, 9”, 12”, 16”, 20”.
The photo above shows a supply tube specifically designed for toilets, most commonly known as a "toilet supply". Notice the plastic 0.5-inch nut, this is the easiest way to recognize this type of supply.
Tools You Will Need to Removing a Toilet
- Measuring tape
- Kneepads or a kneeling pad
- 2 small crescent wrenches
- Long standard screwdriver
- Groove joint pliers also known as channel locks
- Small metal saw
- Box knife
- Small drywall taping knife
- Hand truck
- Disposable polypropylene gloves
- A safe cleaner/degreasing agent
- Paper towel
- Thick plastic bag or sheet
- Duct tape
Items you will need to remove the water from the old tank and toilet bowl:
- The Best: a large shop vac for liquid.
- Alternate Method: A large sponge and a bucket.
Items You May Need to Install Your New Toilet
- Wax ring, standard or barrel. Buy two standard and one barrel wax ring.
- Supply tube.
- An assortment of toilet bolt kits stainless steel and brass with extra washers and nuts.
- High-quality tank-to-bowl bolts. Most kits come with three bolts and accessories.
- Colored or clear tub and tile caulking.
- 100% clear silicone seal.
Remember, you can always return what you don’t you use.
How to Shut the Water Off to Your Entire Home
This is extremely important. You must know how to shut the water off to your entire home. Properly plumbed homes come with a whole house shut off. The possible locations are:
- In the basement near the wall facing the street.
- Under the home in the crawl space, most likely toward the front of the home.
- Within 2 feet of the front of home underneath a lid inside a compartment.
- Homes on wells have too many different configurations to name here. As a “do it yourself-er” you probably already know how to shut your system off.
If you cannot find your whole-house water shutoff, most water service jurisdictions will ask you to call them to shut your water off from the street service at your water meter. If this is not required you can purchase an inexpensive water meter key at your local hardware store. Please call your water service provider for further instructions on this point.
It is not necessary to turn the water off to your entire home to replace the toilet. Knowing how is only a precaution if something goes wrong.
Toilet Replacement Steps
First and foremost, put on your disposable gloves!
1. Turn the water off to your toilet.
Behind the toilet, you will find a small valve. The two common valves are a ¼ turn valve and the gate valve. A shut off valve for a single fixture is usually called a stop valve or simply a “stop”. Dramatic plumbers may call it an emergency valve.
2. Flush the toilet
and hold the handle down until the water stops moving in the tank and bowl. Note; if the tank continues to fill there may be a problem with your shutoff valve. At that point, you may consider turning the water off to your home or replacing the valve. Replacing a faulty valve is always the quality option.
Extremely important; if you decide to shut the water off to your home, you must turn the water supply off to your water heater. This will not affect your water heater, but will save it from possibly draining out and burning out the water heater. This precaution is a “better safe than sorry” precaution. You do not need to turn your water heater off completely by shutting off the power or the fuel supply.
3. Remove the remainder of the water from the tank and the bowl.
Use the shop vac to make this a quick job. Depending on the size of the shop vac and how much water is left in the tank and bowl, you may have to empty the water from the shop vac more than once. No matter how dry you get it, there will always be some water left. Be prepared for some water to spill on the floor.
If you do not have a shop vac, use a sponge and bucket to sop up as much water as you can. When you are through, it is best to throw the sponge away so it will not mistakenly be used for cleaning purposes.
4. Disconnect the supply tube from the shutoff (or stop) valve.
There's usually no need to remove it from the toilet. Paper towels come in handy at this point, there will be a little water spillage. The most common size supply tube connection to the valve is 3/8 inch hexagon compression nut. If you're not sure what the size is, or it is not 3/8 inch, you can always remove the supply tube and take it with you for comparison when purchasing a new supply tube.
5. Remove the nuts from the toilet bolts.
Usually, there are two white caps covering the toilet bolts at the base of the toilet that need to be removed first. Most are plastic (though some older toilets have porcelain caps), unless you intend to reuse them, don't worry about breaking them. Your new toilet will come with new caps. To remove them shove a screwdriver underneath them then twist the screwdriver and they should pop off. If that does not work, grab and squeeze them with large groove joint pliers (channel locks) until they pop off or break. Then remove the nuts and washers so only the bolts are left.
If the nuts are extremely rusted they may crumble. If they're not that bad, spray them with a product like WD 40 then go take a half-hour break to let it soak into the threads. Note; always read labels on products like WD 40 and follow their safety recommendations. This might be a good time to follow step nine, “Assemble your new toilet”.
6. Remove the toilet.
A well installed toilet always has a bead of sealant around the outer edge of the foot of the toilet where the porcelain meets the floor. Using a box knife cut through that sealant using the porcelain as your guide, not the floor. Cut cautiously as not to damage the floor. Have a piece of plastic ready on the floor close by to set the toilet on.
A toilet is heavy, never lift with your back, always with your legs. To do this you must straddle the toilet facing the back of the toilet. Position your body over the portion of the toilet where the toilet seat is connected to the toilet bowl. This is where you will also place your hands to grab and lift the toilet. Grab the toilet, sink through your knees, straighten your back and lift with your legs. If the toilet is being stubborn, you may have to rock it side to side to loosen it from the floor. If the bathroom floor is old, be cautious not to pick the floor covering up, like linoleum tiles. A stuck toilet is common; usually, an extra box knife work will free it from the floor.
6a. Don't be a hero and twist your back. It may look funny but it can save you some pain. With the toilet hanging under you, waddle over to the plastic you have prepared on the floor and place the toilet on that. Again, there may be some water spillage.
6b. With the duct tape, tape the plastic up against the bowl. This will prevent any leakage on the floor in your home when you move the toilet outside. Use your handcart to move the toilet from this point on. It is a little slippery and unwieldy, a helper would come in handy to help you to stabilize and move the toilet outside.
7. Clean the toilet flange.
using the small drywall taping knife, paper towel and degreaser. Remove as much of the old wax ring as you can, be carful where you put it, wax is very sticky and hard to clean up.
8. Install new toilet bolts.
If your toilet flange is plastic, remove the toilet bolts. This is also the perfect opportunity to clean the area of the floor where the old toilet has been sitting. If your toilet flange is cast iron, the toilet bolts may snap off when attempting to remove them. Note; do not put your channel locks directly on the threads this will ruin the threads and make the bolt unusable.
Your first attempt to remove these bolts should be with the double nut method. Place two nuts on the bolt and thread them down to where there is approximately one nut distance from the flange. With two wrenches tighten the nuts together turning the top nut clockwise and the bottom one counterclockwise. You can use some force here. Grabbing the bottom nut with a crescent wrench turn it counterclockwise, this should force the bolt out without damaging the threads.
There is no guarantee that this bolt will not snap. If it does, you will need a re-thread kit and an electric drill to install a new bolt. Usually, instructions come with such a kit.
Turn the bolt counterclockwise to unthread it out of the flange. If this becomes difficult or it won’t budge, use WB 40 on the threads and let it soak in for a ½ hour. At this point, you must make a decision, reuse or replace. If you can replace them, do. Most hardware stores carry the all thread style toilet bolt kits specially designed for cast iron flanges.
Place the bottom lip of the toilet bolts between the floor and the flange, in the location of the original bolts. Using a washer and a nut, tighten and secure the bolts to the flange. Make sure these bolts are centered on the flange and equally distant from the back wall to the bolt. If you have chosen to reuse the bolts in the cast iron flange make sure to use new stainless steel washers and nuts when securing the toilet bowl to the flange.
9. Assemble your new toilet.
This step can be done at any point before step 10. If you have chosen a one-piece toilet, this step is done. If you have chosen a two-piece toilet where the tank-to-bowl bolts go through holes at the bottom of the tank, do as their instruction asks, except add one thing; cover the rubber washers with a healthy coat of 100% clear silicone seal. This helps protect the rubber washers from corrosion and corrects any flaws in the porcelain, bolts or rubber that may cause a leak in the future. Note; silicon seal is very sticky so try to stay as neat as possible and be careful what you touch with your gloved hands after.
Note: Some companies skimp on the quality of tank-to-bowl bolts. Unless you are sure the quality is high, it is recommended to replace these bolts, rubber washers and nuts with brass and/or stainless steel. Kits are available online or from your local hardware store.
9a. Tighten the tank onto the bowl as per the instructions that came with your toilet, while making sure the tank looks perfectly perpendicular with the bowl. Also, watch that the tank and bowl are level with each other horizontally as seen from the front. Do not put the tank lid or seat on yet, these are one of the last steps.
10. Dry fit the toilet onto the flange.
With the same lifting technique, place the toilet on the flange so the toilet bolts protrude through the two holes at the base of the toilet bowl. This is the time to check that you have enough bolt thread sticking up above the porcelain base to comfortably install a washer and nut. If the porcelain base of the toilet is too fat or the toilet flange too low, the toilet bolts may be too short. Extra long bolts are available at most local hardware stores. This will remedy the problem.
This dry fit is also to make sure the footprint of the toilet is in direct contact with the floor. Sometimes there's not enough space underneath the toilet and the toilet rests on the flange and not on the floor. The toilet will begin to wobble and if installed in this condition the toilet will lose its wax seal and may cause water damage.
Two things that can be done to fix this problem.
- Adjust the flange height by removing it and replacing it with a new one. This should be done by a plumber and guaranteed. This is not very cost effective but if the toilet you have chosen is absolutely the one you want then this must be done.
- Purchase a toilet with a deeper cavity inside the footprint of the toilet bowl. Choose a knowledgeable sales representative who can offer you options.
11. Secure the toilet to the flange.
Remove the dry fit toilet from the flange. Wetting down your gloved hands with water will stop the wax from sticking to your gloves. Place the wax ring centered on the flange, don't worry if it rubs up against the toilet bolts. Toilet installation instructions usually recommend placing the wax ring on the toilet first, not many plumbers do this. It makes the job much harder than it needs to be. Make sure your wax ring is at room temperature before placing the toilet on it.
Note: A cold wax ring can split when squished, causing a leak and possibly water damage.
At this point, you can take off your protective gloves and throw them away.
11a. Carefully lower the toilet back onto the flange using the bolts as a guide. It is not easy maneuvering a toilet in this fashion, having a helper guide the toilet can make this step easier.
It is very important that the toilet lands on the wax first before the outer edge touches the floor. It will feel like a soft landing, different than when you did the dry fit. Keep the toilet level and allow the toilet’s own weight to slowly squish the wax ring. After a few minutes, you can help it along by sitting backward on the toilet, using your own weight until the footprint of the toilet rests firmly on the floor. Visually inspect that the toilet bowl is straight out from the wall. If not, you can slightly twist it on the flange as far as the bolts will allow.
11 b. Place your level on the rim of the toilet bowl from left to right to make sure the toilet bowl is plumb. If it is not, use plastic shims to level it. (see the bottom of this article for additional shimming info.) Use the washers and nuts to tighten the bowl to the flange. If you have plastic caps for the bolts the instructions may require you to place a plastic washer designed for the caps under the nut. Be sure to get the correct side up on those plastic washers.
12. Install the supply tube.
Thread and tighten the 3/8 end of the supply tube to the toilet shutoff valve. Then thread and hand tighten the larger half inch end of the supply tube to the threaded portion of the fill valve that protrudes from the bottom of the tank. Use a wrench to tighten it an extra half turn or 180°. The best supply tube to use has a steel mesh outer casing, with a special 1/2 inch nut specifically designed for toilets. Dramatic plumbers called this style of supply tube with the steel mesh “burst proof”.
13. Slowly turn on the water to the tank, while watching for leaks.
Any leaks on the supply tube will require extra tightening until the drip is stopped. If no leaks are detected, turn the valve on completely and allow the tank to fill normally. Move your hand around to the back of the tank and underneath it to feel for any leaks or water where you cannot see. When you are satisfied there are no leaks at this point, flush the toilet. Check for leaks between the tank and the bowl, and the bowl and the floor. Flush the toilet several times and make absolutely sure.
14. Finishing up.
14 a. Place the tank lid on the tank.
14 b. Because there are many different styles of seats, read the instructions that come with the toilet seat. Install the toilet seat as per instructions but only finger tighten the bolts. Make sure the seat is positioned perfectly centered over the porcelain rim, and then tighten the bolts very tightly. Even though those bolts are very tight, plan to tighten them at least once a year, they almost always work themselves lose.
14 c. With the small hacksaw, cut the toilet bolts to length, one or two threads above the nut. Use a wet cloth to clean up the metal filings then place the caps over the bolts. The plastic caps with the plastic washers snap on by pressing them down firmly. The other style requires a bead of sealant or caulking to adhere the base of the cap to the porcelain.
14 d. Make sure the floor is clean and dry, then place a thin bead of caulking around the base of the toilet. Using a wet finger and a piece of paper towel, run your finger along the base against the porcelain and the floor simultaneously, then wipe your finger off on the paper towel. Keep doing this until you have a very sharp almost invisible bead of caulking around the base of the toilet. Clear caulking starts out white then will dry clear. This is goof proof caulking, any mistake you make will disappear when it dries up. Any other color you use will start out as that color and of course dry as that color. It is better not to use the toilet until the caulking is dry.
Some of the Problems You May Run Into
Plastic shims may need to be used if the floor of the bathroom is uneven. Always start by shimming the back of the toilet first, then work your way around. Shims in front of the toilet are much more noticeable than ones in the back. Before you tighten the toilet to the flange, use a level on the rim of the bowl to make sure the toilet is plumb. Do not use wood shims, if they get wet they become soft and rot. Once the shims are set, cut them off flush with the porcelain.
If you don't feel the wax ring squish when you place the toilet, this means that the distance from the flange to the bottom of the toilet is more than the thickness of your wax ring. The solution is to use a fatter barrel type wax ring or stack two standard wax rings on top of each other on the flange.
If you have chosen to turn off the water supply to your home, standard water pipes will not cause a problem. All the way up and into the 1970s galvanized pipe was installed in new homes of that time. The big problem with this pipe is that it rusts from the inside out. Shutting off the water to your home reduces the outward pressure on these pipes causing them to shrink slightly, causing the rust on the inside to flake off. This can cause low or even stopped water flow to your fixtures due to clogging.
The only way to stop this problem is by either replacing all the pipes in your home or not shutting the water off to your home. If you have a persistent orange ring around your toilet, you’re constantly cleaning the rust out of your aerators or you have to wait a minute for your water to turn from orange to clear, then you have galvanized pipes.
Older homes with copper pipes have a common problem. Shutoff valves like the one for your toilet are installed using compression. Solder joints last forever, a compression joint actually digs into the copper creating a weak point. Over time the scouring properties of water will thin the edge portion of the copper pipe where the compression joint has created a bulge on the inside circumference of the pipe.
Experienced plumbers will turn off the water to the house before attempting to shut off the water to an individual fixture with a compression-style valve. Some plumbers will carry what is called a “jet sweat” with them so if the shutoff valve does break off in their hand they can quickly insert the tool into the pipe and with a few twists of the handle close off the pipe avoiding a flood.
This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.
Questions & Answers
© 2011 Rob S