How Much Water Does an Old Toilet Use?
Buying GuidesFind out how many gallons per flush an old toilet really uses, how to check your own tank, and how much water…
Read the guideA complete checklist of every tool and supply you need to install or replace a toilet correctly -- from the wrench you already own to the wax ring you absolutely cannot skip. Get the list right the first time and avoid a second trip to the hardware store.
Research updated June 2026.
For a standard toilet swap you need an adjustable wrench, channel-lock pliers, a putty knife, a wax ring (or wax-free seal), a new supply line, a sponge, and a bucket. A cordless drill, level, and hacksaw are helpful but rarely required. Budget 60 to 90 minutes for a like-for-like replacement with no plumbing changes.
Replacing or installing a toilet is one of the most approachable plumbing jobs a homeowner can tackle. The rough-in dimensions are almost always standard, the water supply connection is forgiving, and the job does not require soldering, threading pipe, or cutting into walls. What it does require is showing up with the right tools. A missing basin wrench or an improperly sized wax ring is the difference between a clean two-hour job and a half-day scramble back to the hardware store with the water shut off.
This guide covers every tool and consumable supply you need, explains why each one matters, and flags the substitutions that work versus the ones that waste time. Whether you are swapping out a tired builder-grade toilet for a best flushing toilet or doing a full bathroom rough-in, the checklist below will get you there without surprises.
The minimum toolkit for a standard toilet replacement is: adjustable wrench, channel-lock (slip-joint) pliers, putty knife or plastic scraper, sponge and bucket, wax ring or wax-free seal, new braided stainless supply line, and rubber gloves. A cordless drill helps with anchoring bolts to wood flooring, and a level is useful for shimming on uneven floors, but neither is strictly required for most swaps.
The list can look overwhelming when you read it all at once, but most items fall into one of three buckets: tools you likely already own, consumable supplies you buy once per installation, and specialty tools that solve specific problems. We cover all three categories below.
Professional plumbers note that the single most common DIY toilet installation failure is an improperly seated wax ring. The ring must contact both the toilet horn and the flange collar at the same time, under even pressure. Getting that right depends less on technique than on choosing the correct ring thickness for your flange depth -- something no wrench can fix after the fact.
An adjustable wrench (10-inch or 12-inch) handles the supply line nuts and tank bolt nuts on most toilets. Channel-lock pliers provide extra grip on plastic nuts that seat too tightly for a standard wrench. A putty knife or plastic scraper is essential for removing the old wax ring from the flange without gouging the porcelain or the floor flange.
Here is what each hand tool actually does during an installation:
| Tool | Required or Optional | Used For | Substitute If Not Available |
|---|---|---|---|
| Adjustable wrench (10-12 in) | Required | Supply line, tank bolt nuts | Open-end wrench, matching size |
| Channel-lock pliers | Required | Plastic nuts, closet bolts | Locking pliers (less ideal) |
| Putty knife or scraper | Required | Old wax ring removal | Plastic drywall knife |
| Hacksaw or mini hacksaw | Often required | Trim excess closet bolt shank | Oscillating tool with metal blade |
| Flathead screwdriver | Required | Hold closet bolt, pry bolt caps | None -- keep one in the kit |
| Cordless drill + bits | Optional | Shim screws, anchor new flange | Hand screwdriver (slow) |
| Torpedo level | Optional but useful | Check toilet is plumb side-to-side | Smartphone level app |
| Tape measure | Required before purchase | Confirm rough-in dimension | Folding rule |
You need a wax ring (standard or thick, matched to your flange depth), a new flexible braided stainless supply line (12 or 16 inches, with a 3/8-inch compression-to-7/8-inch ballcock fitting), new plastic or brass bolt caps to cover the closet bolts, and plumber's tape (PTFE/Teflon tape) for any threaded connections. Buy these new each time; do not reuse an old wax ring or a supply line from a previous installation.
Consumables are the items that go directly between the toilet and the floor or the water supply. Unlike tools, they are single-use and must match the specific installation.
The wax ring forms a watertight, gas-tight seal between the toilet horn (the outlet at the base of the toilet) and the floor flange (the fitting bonded to the drainpipe). It is not reusable. Every time you lift a toilet -- even just to check for a leak -- you must install a new wax ring when you reset it.
Wax rings come in two main thicknesses:
Wax-free seals (silicone or foam-based alternatives such as the Fernco Wax Free Toilet Seal) are gaining traction in the plumbing trade because they can be repositioned if the toilet shifts during installation. They perform well on flush or above-flush flanges, but most product instructions advise against them on deeply recessed flanges where added height is genuinely needed.
Plumbers who specialize in renovation work note that roughly 30 percent of toilet replacements require a thick wax ring because floor tile or LVP has been laid without raising the flange. Measure the distance from the top of the flange collar to the finished floor surface before buying. If the flange is more than 1/4 inch below floor level, go thick or use a flange extender ring in combination with a standard wax ring.
A braided stainless steel supply line is far more durable than the old ribbed-plastic lines still sold in some discount stores. Most toilet fill valves use a 7/8-inch slip-joint (ballcock) fitting at the tank end and a 3/8-inch compression fitting at the shutoff valve. Confirm both measurements before you buy.
Common supply line lengths are 9, 12, 16, and 20 inches. Measure from the center of the shutoff valve outlet to the fill valve inlet on the tank bottom. Add about 2 inches of slack so the line does not run fully taut. A line under tension is more likely to develop micro-cracks at the fitting over time.
A toilet flange repair kit is only needed if the existing flange is cracked, corroded, or sitting too low relative to the finished floor. For a straightforward like-for-like toilet swap on an intact flange, no repair kit is required. If the flange has a crack wider than 1/8 inch, or if the closet bolts no longer anchor solidly, repair the flange before proceeding -- a failed flange is the leading cause of persistent toilet leaks at the base.
Toilet flanges fail in three common ways: the plastic body cracks (especially on older ABS flanges in cold climates), the metal collar corrodes through, or the flange sits too low after flooring upgrades. Each failure mode has its own solution:
If you are replacing a TOTO Drake, Kohler Highline, or American Standard Champion 4 and the existing flange is intact and flush with the floor, you will almost certainly not need a repair kit. Inspect the flange after you remove the old toilet and before you purchase any repair parts.
Before starting a toilet installation, you need rubber or nitrile gloves, a large sponge and a bucket (to remove standing water from the tank and bowl), old towels or a drop cloth for the floor, and eye protection if you are cutting bolts with a hacksaw. A garbage bag for the old wax ring and another for soiled rags keeps the work area hygienic.
Preparation is underrated in most tool-list guides, but it directly affects installation speed and cleanliness. Here is what to have in place before you lift any tools:
Plumbers commonly note that the second most frequent mistake homeowners make -- after choosing the wrong wax ring -- is failing to fully remove water from the toilet bowl before lifting. Even after flushing, a toilet bowl holds roughly a quart of water in the trap. That water will pour across your floor the moment the toilet tilts past horizontal. Sponge out as much as possible, then use a wet-dry shop vac if you have one. Five minutes of prep prevents 20 minutes of mopping.
Rough-in distance is measured from the finished wall behind the toilet (not the baseboard) to the center of the closet bolts (or the center of the flange, if the old toilet is already removed). The standard rough-in in U.S. homes built after 1960 is 12 inches. Older homes may have 10-inch or 14-inch rough-ins, which require a specific toilet model to match. A toilet with a 12-inch rough-in will not seat correctly on a 10-inch flange.
Getting the rough-in measurement right before you purchase a replacement toilet saves a return trip to the store. The measurement itself takes about 30 seconds with a tape measure:
Most toilets from major brands -- the TOTO Drake (model CST744SL), TOTO UltraMax II, Kohler Cimarron, American Standard Cadet 3, Woodbridge T-0001, Swiss Madison Sublime, and Gerber Viper -- are built for a 12-inch rough-in by default. TOTO and Kohler offer select models with 10-inch and 14-inch rough-in variations if your situation requires them. See our toilet rough-in measurement guide for more detail.
Use the following checklist to confirm you have everything before turning off the water supply. Printing it or keeping it open on your phone during a hardware store run will prevent most mid-job surprises.
| Item | Category | Notes | Have It |
|---|---|---|---|
| Wax ring (correct thickness) | Consumable | Match to flange depth -- standard or thick | Buy new each time |
| Braided stainless supply line | Consumable | 3/8 comp x 7/8 ballcock; measure length first | Buy new each time |
| Adjustable wrench (10-12 in) | Tool | Most common tool used in the job | Likely already own |
| Channel-lock pliers | Tool | For plastic nuts and closet bolt gripping | Likely already own |
| Putty knife or plastic scraper | Tool | Remove old wax ring residue | Likely already own |
| Hacksaw or mini hacksaw | Tool | Trim excess closet bolt shank | May need to purchase |
| Flathead screwdriver | Tool | Hold bolt slot, pry caps | Likely already own |
| PTFE (Teflon) plumber's tape | Consumable | Threaded connections only | Buy if not on hand |
| Sponge and bucket | Preparation | Remove residual tank/bowl water | Likely already own |
| Rubber or nitrile gloves | Safety | Use throughout the job | Buy a box if needed |
| Garbage bags (2) | Preparation | Old wax ring + soiled rags | Likely already own |
| Drop cloth or old towels | Preparation | Floor protection | Likely already own |
| Torpedo level | Tool (optional) | Confirm toilet seats level side-to-side | Optional -- or use phone |
| Plastic toilet shims | Consumable (as needed) | Stabilize toilet on unlevel floor | Buy a pack -- inexpensive |
| Flange repair ring (as needed) | Consumable (as needed) | Only if flange is cracked or recessed | Inspect flange first |
Two-piece toilets (separate tank and bowl, such as the TOTO Drake, Kohler Highline, and American Standard Champion 4) require a few extra steps compared to one-piece models (TOTO UltraMax II, Woodbridge T-0001, Swiss Madison Sublime). The tank must be bolted to the bowl using tank bolts, rubber gaskets, and plastic or brass mounting bolts -- all typically included in the box but worth confirming before you open the carton.
For a two-piece installation, additionally have ready:
One-piece toilets are heavier (often 80 to 120 pounds versus 50 to 70 pounds for a two-piece bowl alone) and may require a second person to maneuver into position. Have a helper confirmed before you start.
If you are evaluating which toilet type to install, our guide to one-piece vs. two-piece toilets covers the tradeoffs in detail, and our rough-in measurement guide walks through how to confirm fit before you buy.
For the TOTO Aquia IV dual-flush toilet, installation follows the same tool list as any two-piece, but the tank-to-bowl connection uses a rubber spud washer that must be centered perfectly to avoid weeping leaks between tank and bowl. TOTO includes alignment instructions in the box; read them before connecting the tank. This applies equally to any dual-flush toilet from Kohler or American Standard that uses a tower flush valve rather than a flapper.
A standard toilet replacement -- same rough-in, intact flange, shutoff valve turns freely -- is confidently in DIY territory for most homeowners. You need a licensed plumber when:
If your inspection after removing the old toilet reveals any of the above, stop and call a plumber before proceeding. Installing a toilet on a compromised flange or rotted subfloor will result in another failure within months. See our guide to toilets leaking at the base for a step-by-step diagnosis of what went wrong with the previous installation.
The tools you use matter less than the toilet you select. EPA WaterSense-certified toilets use 1.28 gallons per flush (GPF) or less and must pass a minimum 350-gram MaP (Maximum Performance) flush-test score. High-performing models routinely score 500 to 1,000 grams on MaP testing, meaning they clear that weight of solid waste in a single flush.
MaP testing is conducted by independent labs using standardized test media. Scores are publicly searchable at map-testing.com and are a more reliable predictor of real-world performance than manufacturer claims. When choosing among the TOTO Drake II (MaP score: 1,000 grams), American Standard Champion 4 (MaP score: 1,000 grams), Kohler Cimarron (MaP score: 1,000 grams), or Gerber Viper (MaP score: 800 grams), the MaP score tells you exactly how the toilets compare on clog resistance -- before you spend time installing one that underperforms.
No special wrench is required. A standard 10-inch or 12-inch adjustable wrench handles the supply line nut and tank bolt nuts on virtually all residential toilets. Channel-lock pliers handle plastic nuts that a wrench jaw cannot grip flat.
No. Wax rings are single-use only. Once the toilet is lifted, the ring is compressed and deformed and will not form a reliable seal when reused. Always install a new wax ring every time a toilet is reset, even if you only lifted it briefly.
Most residential toilets use a 3/8-inch compression fitting at the shutoff valve and a 7/8-inch slip-joint (ballcock) fitting at the fill valve on the tank bottom. Measure the distance between the two connections and buy a braided stainless line 2 inches longer than that measurement to allow for a slight curve.
Measure from the top surface of the floor flange collar to the finished floor surface. If the flange sits flush with or up to 1/4 inch above the floor, use a standard ring. If it sits more than 1/4 inch below the finished floor, use a thick ring or stack a flange extender ring with a standard ring.
For flush or above-grade flanges, wax-free silicone and foam seals (such as the Fernco Wax Free Seal) perform comparably to wax rings in long-term plumbing assessments and have the advantage of allowing repositioning during installation. They are not recommended for deeply recessed flanges where added height is needed.
In most cases you only need to close the angle stop (shutoff valve) directly behind the toilet. Only turn off the main supply if the angle stop is stuck, corroded, or does not fully seat. If you need to replace the angle stop itself, the main supply must be shut off.
The standard rough-in in homes built after approximately 1960 is 12 inches, measured from the finished wall to the center of the floor flange. Older homes sometimes have 10-inch or 14-inch rough-ins. Confirm the measurement before purchasing a replacement toilet, as most stock models are 12-inch only.
Local plumbing codes vary. Some jurisdictions require caulking around the toilet base; others prohibit it because caulk can conceal a wax ring leak. If you caulk, leave the back 1 to 2 inches open so any future leak is visible. Use 100% silicone rated for wet areas.
Technically yes, but it is difficult. One-piece toilets typically weigh 80 to 120 pounds. Maneuvering that weight while aligning the horn over the flange and lowering evenly onto the wax ring is significantly easier with two people. Attempting it alone increases the chance of a misaligned wax ring seat.
Closet bolts have a square shank that is designed to catch in the flange slot and prevent spinning. If the bolt spins, either the slot is damaged or the bolt has not been seated correctly. Press the bolt shank firmly into the slot while holding it with a flathead screwdriver from above, then start the nut again by hand before using pliers.
Tank bolt nuts on porcelain toilets should be tightened only until the rubber washers compress and stop the tank from rocking -- typically just snug plus a 1/4 turn. Over-tightening is the leading cause of cracked toilet tanks and is irreversible. Alternate between the two bolts in small increments to apply even pressure.
A rocking toilet is almost always caused by an unlevel floor, not an improperly installed toilet. Slide plastic toilet shims under the base in the direction the toilet rocks until it sits stable. Shims are typically trimmed flush with the base edge and can be caulked in place. Do not over-tighten the closet bolt nuts to compensate -- that is how flanges crack.
Compression fittings (the 3/8-inch end at the shutoff valve) do not require Teflon tape -- the compression ferrule creates the seal. Threaded connections do benefit from 2 to 3 wraps of PTFE tape. Check your specific supply line and fill valve instructions, as some fill valve locknut threads are designed to seat without tape.
EPA WaterSense is a voluntary labeling program run by the U.S. Environmental Protection Agency. Toilets bearing the WaterSense label use 1.28 GPF or less and must pass an independent flush-performance test. According to EPA data, replacing a 3.5 GPF toilet with a WaterSense model saves an average household about 13,000 gallons per year.
MaP (Maximum Performance) testing is an independent laboratory evaluation that measures how much solid waste a toilet can clear in a single flush, expressed in grams. Scores range from 250 grams (minimum threshold) to 1,000 grams (the highest rating). Results are publicly searchable by model number at map-testing.com and are the most reliable third-party data point for comparing toilet performance across brands.
Yes. On a concrete floor, the flange is typically a cast-iron or PVC fitting set into the concrete. The installation process is identical -- wax ring, set the toilet, tighten closet bolt nuts. If you need to relocate the drain on a concrete floor, that involves cutting concrete and is a job for a licensed plumber.
A cracked flange cannot anchor the closet bolts reliably, which causes the toilet to rock and eventually compress the wax ring unevenly, leading to a base leak. Repair options include a stainless steel repair ring that bolts over the existing flange (the easiest fix), or full flange replacement if the damage is severe. Do not install a new toilet on a cracked flange without addressing the repair first.
A standard like-for-like toilet replacement with all tools and supplies on hand takes most homeowners 60 to 90 minutes. The majority of that time is removing the old toilet, cleaning the flange, and managing water removal. The actual assembly and setting of the new toilet takes 20 to 30 minutes.
Yes, significantly. Wall-hung toilets require a steel carrier frame embedded in or mounted to the wall, which involves drilling into studs, setting a concealed cistern (tank), and anchoring support rods to the floor. The tool list expands to include a stud finder, rotary hammer or impact driver, masonry bits (for tile walls), and a torque wrench for the carrier bolts. This is beyond a typical DIY swap and often requires a plumber.
It is not required, but it is a practical opportunity. If the existing angle stop valve is more than 10 to 15 years old, corroded, or hard to turn, replacing it while the water is already off and the toilet is out adds minimal time and avoids a future emergency. Quarter-turn ball-style angle stops are more reliable than the older compression stop valves found in homes built before the mid-1990s.
A standard toilet replacement requires only tools most homeowners already own -- an adjustable wrench, channel-lock pliers, a putty knife -- plus two consumables you must buy fresh each time: a correctly sized wax ring and a new braided stainless supply line. Invest five minutes confirming your rough-in dimension and flange depth before purchasing, and the remaining installation is straightforward for a careful DIYer working within 60 to 90 minutes.
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Researched by Marcus Bell · Last updated August 14, 2026 · Our review method
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