Types of Toilets: How to Choose the Right One

Three choices, construction, mounting, and flushing, tell you what toilet type fits your home: one-piece or two-piece, floor-mount or wall-hung, and single-flush or dual-flush. Those choices overlap, so a toilet can be, for example, a two-piece, floor-mounted, dual-flush model. Start by confirming your existing plumbing and available space, then choose the shape, height, and flush system that suit the people using it.

Understand the Three Toilet Type Decisions

A toilet is a combination of construction, mounting, and flushing choices, not a single fixed category.

Construction: One-Piece or Two-Piece

A one-piece toilet has the tank and bowl molded together. Its smooth exterior has fewer seams to clean, and it often has a more streamlined appearance.

A two-piece toilet has a separate tank and bowl. This is the familiar style in many homes and can be practical when replacing an existing standard toilet. The tank and bowl connection creates one more exterior seam to clean, but there are many styles and replacement options.

Mounting: Floor-Mount or Wall-Hung

A floor-mount toilet bolts to the bathroom floor and connects to a floor drain. It is the usual choice for a straightforward replacement because it works with the plumbing already present in most homes.

A wall-hung toilet attaches to a concealed in-wall carrier, with the tank hidden inside the wall. It leaves the floor underneath open for easier cleaning. It is usually best suited to a major bathroom remodel because the wall must be opened and properly framed for the carrier and tank.

Flushing: Single-Flush or Dual-Flush

A single-flush toilet uses the same amount of water every time you flush. It is simple, familiar, and available in the widest range of toilet styles.

A dual-flush toilet gives you a lighter flush and a full flush. The two buttons or split handle can reduce water use when the lighter flush is appropriate, but compare the actual water-use specifications rather than choosing based on the dual-flush label alone.

How to Choose the Right Toilet for Your Home

Compare construction, mounting, bowl projection, and flush system before you shop. Then take the measurements in order, because a toilet that looks right still has to match your drain location, wall framing, and bathroom clearance.

Decision	Common Choices	Best Fit	What to Verify
Construction	One-piece or two-piece	One-piece for a sleeker, easier-to-wipe exterior; two-piece for a conventional replacement style	Tank-and-bowl configuration and exterior shape
Mounting	Floor-mount or wall-hung	Floor-mount for most replacements; wall-hung for a remodel with wall access	Drain rough-in for floor models; carrier and framing for wall-hung models
Bowl projection	Round-front or elongated	Round-front for tight rooms; elongated for more seating room	Round-front lengths of 25⅝ to 29¾ inches and elongated lengths of 28½ to 31⅝ inches; check the selected toilet’s product dimensions
Flush system	Single-flush or dual-flush	Single-flush for one consistent action; dual-flush for two water-use options	The model’s stated flush volume and WaterSense label

Step 1: Measure the Plumbing Before Choosing a Mounting Style

For a floor-mounted toilet, measure from the finished wall, not the baseboard, to the center of the floor bolts holding the toilet down. This is the rough-in measurement, and it determines whether the new toilet will line up with the existing drain.

A 12-inch rough-in is most common, but 10-inch and 14-inch rough-ins also exist. Match the toilet to the measurement you have rather than assuming every floor-mounted toilet will fit. Kohler’s toilet buying guide includes floor-mounted models and sizing guidance for these rough-in options.

For a wall-hung toilet, check the depth of the wall studs before selecting an in-wall tank and carrier. Kohler in-wall tank systems are made to coordinate with either 2-inch by 4-inch or 2-inch by 6-inch studs, so the tank system must match the framing already in the wall or the framing planned for the remodel.

Step 2: Choose a Bowl Shape That Leaves Enough Clearance

A round-front bowl is the practical choice when the bathroom is narrow or the toilet sits near a door, vanity, or shower entrance. An elongated bowl usually provides more room for the user, but it projects farther into the room.

Use the product drawing for the exact toilet you want, not just the category name. Measure from the finished wall to the furthest point the new toilet will reach, then make sure doors, drawers, and people can move through the space comfortably. Also check the overall fixture depth, since the listed bowl format alone does not account for every part of the toilet.

Step 3: Match the Toilet Height to the Users

Measure toilet height from the finished floor to the top of the seat, not merely to the top of the porcelain bowl. Most toilets fall between 15 and 19 inches at the seat. Standard-height toilets are under 17 inches, while chair-height toilets measure 17 inches or more.

Chair-height toilets can make sitting down and standing up easier for many adults, particularly people with limited knee or hip mobility. They are not automatically the best choice for every household, though: shorter adults and children may prefer a lower standard-height seat.

Wall-hung systems offer the most height flexibility. Kohler wall-hung toilets can be set from 15⅜ to 28½ inches high, depending on the selected system. Confirm the supported mounting-height range in the specifications for the exact carrier and bowl before installation.

Step 4: Compare the Flush Volume and Water-Saving Options

A single-flush toilet typically uses 1.0 to 1.6 gallons per flush. This can be a good choice when you want a familiar handle-operated toilet and one predictable flush setting.

Dual-flush toilets provide two settings. On Kohler dual-flush models, a light flush can use as little as 0.8 gallons, while a full flush can use up to 1.6 gallons. Check both figures on the exact model you are considering, because the light-flush and full-flush volumes vary by toilet.

Choose a model with a flush system that feels simple enough for everyone in the home to use correctly. A water-saving toilet should still clear the bowl reliably; repeated flushing defeats much of the intended water savings.

Step 5: Select One-Piece or Two-Piece Construction Last

Once you know the rough-in, mounting style, bowl projection, height, and flush system, choose the exterior style you prefer.

Pick a one-piece toilet if easy exterior cleaning and a compact, integrated look matter most. Pick a two-piece toilet if you want the conventional tank-and-bowl arrangement used in many homes and a broad range of style options.

If you are replacing an existing toilet rather than remodeling, a floor-mounted two-piece toilet is often the simplest path because it usually works with standard plumbing arrangements. That does not make it automatically better than a one-piece model; fit and flush performance matter more than the number of pieces.

Choose the Best Toilet Type for Your Bathroom

For a Typical Toilet Replacement

Choose either one-piece or two-piece construction based on your cleaning preference and the look you want.

A WaterSense-labeled toilet is a strong starting point if you want a water-efficient replacement that has also met performance requirements.

For a Small Bathroom or Half Bath

Start with the floor rough-in, then favor a round-front bowl if the toilet needs to project as little as possible into the room. A compact one-piece toilet can also make a small bath look less crowded.

Do not rely on a showroom impression. A few inches of projection can determine whether a bathroom door clears the toilet or whether the space feels cramped.

For Aging in Place or Easier Transfers

Consider a chair-height toilet when the main concern is making it easier to sit and stand. Check the finished floor-to-seat measurement with the seat included, especially if you plan to add a thicker replacement seat later.

A wall-hung toilet can be useful in a fully planned accessibility remodel because its height can be set during installation. A wall-hung toilet is not a simple swap-in project, though, because the carrier must be securely installed inside the wall.

For a Modern, Easy-to-Clean Bathroom

A wall-hung toilet makes the floor underneath accessible for cleaning. A skirted floor-mounted toilet can also reduce the hard-to-reach contours around the trapway while keeping the installation simpler than a wall-hung model.

Compare Water Use and Flushing Performance

All new toilets sold in the United States must use 1.6 gallons per flush or less. WaterSense-labeled toilets use 1.28 gallons per flush or less and must meet water-efficiency and flushing-performance requirements.

The WaterSense label is useful because it helps you avoid treating low water use as the only measure of a good toilet.

Some toilets use even less water. Kohler lists certain toilets that use as little as 0.8 gallons per flush, but that is a product-specific figure, not a standard for every toilet.

The Portland Water Bureau’s toilet efficiency guidance covers efficient toilets and leak-related water waste.

Confirm Fit Before Ordering and Know When to Call a Plumber

Before ordering a toilet, make a final check of these points:

Measure the floor-mount rough-in from the wall to the bolt centers.
Confirm whether the wall behind the toilet can accommodate an in-wall carrier and tank.
Check the selected toilet’s complete depth, width, and seat-height specifications.
Make sure doors, vanity drawers, shower doors, and nearby cabinets have enough clearance.
Verify whether the toilet includes a seat and whether the listed height is measured with the seat installed.
Review the flush volume for the exact model, especially with dual-flush toilets.
Take photos of the current toilet, floor bolts, shutoff valve, and nearby walls before shopping.

Assess the existing setup before planning a floor-mounted replacement. Call a plumber for a cracked flange, soft or damaged flooring, a persistent leak at the base, sewer odor, a major drain problem, or a project that requires moving pipes.

Frequently Asked Questions

What are the different types of toilets?

The most useful way to classify toilets is by three decisions: one-piece or two-piece construction, floor-mount or wall-hung installation, and single-flush or dual-flush operation. Bowl shape and seat height are additional fit choices, not separate plumbing categories. A toilet can combine any compatible options, such as a one-piece, floor-mounted, single-flush design.

What type of toilet is best for most homes?

A floor-mounted toilet that matches the existing rough-in is usually best for a straightforward replacement. Choose a round-front model for tighter bathrooms, an elongated model for more seating room, and a WaterSense-labeled model if water efficiency is important. The best construction choice depends on whether you prefer the smooth exterior of a one-piece toilet or the traditional layout of a two-piece model.

Is a one-piece toilet better than a two-piece toilet?

Neither is automatically better. One-piece toilets have a smoother exterior with fewer seams around the tank area, while two-piece toilets use the familiar separate tank-and-bowl design. Both can be efficient, comfortable, and reliable if their dimensions and flush performance match your bathroom and household.

How do I know which rough-in size I need?

Measure from the finished wall, not the baseboard, to the center of the floor bolts. A 12-inch rough-in is common, but toilets are also available for 10-inch and 14-inch rough-ins. Buy a toilet made for the measurement you find rather than trying to force a mismatched model into place.

Are dual-flush toilets worth it?

Dual-flush toilets can be worthwhile when you want a lighter and a full flush option. A dual-flush model may use as little as 0.8 gallons for a light flush and up to 1.6 gallons for a full flush, depending on the model. They work best when everyone using the bathroom understands which control to use.

When should I call a plumber instead of replacing the toilet myself?

Call a plumber if the toilet base leaks, the floor feels soft, the flange is damaged, the drain backs up, or the project involves moving plumbing or installing a wall-hung carrier. For a standard replacement, take your rough-in measurement, room-clearance measurements, and a photo of the existing setup to the store before buying the new toilet.