Rear Outlet vs Floor Outlet Toilets: Which Fits Better?

Start with the drain connection

The first decision is not style, bowl shape, or flush technology; it is where the waste leaves the bowl. A floor outlet toilet drops waste through a flange in the bathroom floor. A rear outlet toilet sends waste backwards through a connection at the back of the bowl. If the new toilet does not match the existing drain, installation stops before you ever sit on it. Learn the basics of toilet flange basics before you compare models.

The useful way to compare the two is to ask what is fixed in your bathroom. For a floor outlet toilet, the fixed part is a floor flange and its rough-in distance from the back wall. For a rear outlet toilet, the fixed part is a wall connection at a specific height and side-to-side position. Check the drain first, then pick the toilet.

Floor outlet toilets: the default choice

A floor outlet toilet is the conventional arrangement in the United States. The bowl sits above a closet flange, and waste moves straight down into the drain pipe. Installation uses closet bolts, a wax ring or gasket, and a floor flange. You can read more in toilet wax ring vs rubber gasket.

For replacements, a floor outlet has a clear advantage. If the floor flange is in good condition and the rough-in still matches, a floor outlet toilet in the same rough-in family can usually be set in place without rerouting drain pipe. That is why most bathroom renovations keep the same floor drain. See toilet rough-in sizes and best 12 inch toilets.

Rear outlet toilets: what changes

With a rear outlet toilet, the discharge opening faces the back wall. The bowl is still a toilet, but the waste pipe connection is behind it. This design may be floor mounted with a wall flange or built into a wall-hung carrier. Because there is no floor flange directly beneath the bowl, the toilet can often sit closer to the wall.

Rear outlet layouts are less standardized. You have to match the outlet height, the horizontal centerline of the wall drain, and the type of connection. Some installations use an adaptor to a conventional wall stub; others require a special carrier or a macerating pump. For the common variants, read wall hung toilet requirements and what is a macerating toilet.

A rear outlet is worth considering when the drain line already runs in the wall, when you want a wall-hung look, or when you are adding a bathroom where running a floor pipe is difficult. It is also the typical outlet for upflush toilets, which pump waste to a distant drain. The trade-off is less flexibility in replacement and more attention to alignment.

How outlet type changes bathroom fit

In a conventional floor outlet bathroom, the bowl position is controlled by the rough-in: the distance from the finished wall to the center of the floor flange. The toilet must sit far enough from the wall to cover that connection, which can leave a visible gap behind the tank. A rear outlet toilet can eliminate that gap because the connection is in the wall, not under the bowl. In a compact room, that can make the toilet feel less intrusive; see compact toilets how to choose.

Do not confuse outlet type with mounting type. A floor outlet toilet is normally floor mounted, but a rear outlet toilet can be floor mounted, wall hung, or part of a macerating unit. The real fit question is drain access: can the plumber reach the connection and does it line up with the fixture?

Accessibility is a separate layer. The 2010 ADA Standards set minimum requirements for newly designed and constructed or altered state and local government facilities, public accommodations, and commercial facilities. Standards issued under the ADA apply to those facilities in new construction, alterations, and additions. The outlet type does not replace those requirements. For a home, apply the same idea by deciding seat height and clear floor space independently.

Replacement and remodeling decisions

If you are replacing an existing toilet, the safest route is to match the outlet type already in place. Changing from floor to rear outlet usually means cutting into a wall, installing a new wall connection or carrier, and rerouting the drain. That is a larger project than a toilet swap. If you are doing that work anyway, a rear outlet can give you a cleaner wall-to-toilet fit and free floor space.

If you are moving the toilet in a remodel, decide the outlet type before you pour concrete or close up walls. For a floor outlet toilet, you need a floor flange set at the correct height. For a rear outlet toilet, you need a wall connection that aligns with the fixture. Use toilet drain pipe compatibility to check the rest of the drain plan.

• Keep the existing floor flange and choose a floor outlet toilet with the same rough-in.
• Build a wall or carrier and choose a rear outlet toilet if you want the bowl tight to the wall.
• Use a macerating unit with a rear outlet if you have to pump waste to a remote drain; see floor-mounted vs wall-hung toilets.

Water efficiency and accessibility are separate

Outlet type does not determine water use. You can find efficient toilets in either connection style. EPA's WaterSense program identifies products that save water, and toilets are by far the main source of water use in the home, accounting for nearly 30 percent of indoor water consumption. Older, inefficient toilets can use as much as 6 gallons per flush, while WaterSense labeled toilets use 1.28 gallons per flush or less, 20 percent less than the federal standard of 1.6 gallons per flush. Within a home, roughly 70 percent of water use occurs indoors, so the fixture you choose matters. After you settle the outlet, look for the WaterSense label and compare flush systems in best 1.28 gpf toilets or best dual flush toilets.

Also decide seat height, bowl shape, and style independently of the outlet. The connection detail says nothing about whether a toilet is round or elongated, one-piece or two-piece, or how high the bowl sits. Build your shortlist from the drain first, then add the features you need.

What to pick for your use

Questions

Can I replace a floor outlet toilet with a rear outlet model?

Usually not without moving the drain. A floor outlet toilet depends on the floor flange beneath it; a rear outlet toilet sends waste into a wall connection. To switch, you generally need to reroute the waste pipe, add a wall connection or carrier, and patch the floor. If the bathroom is built around a floor flange, stay with a floor outlet unless the plumbing is being changed.

Are floor outlet toilets easier to install than rear outlet toilets?

For a like-for-like replacement, yes. A floor outlet toilet sits on an existing flange with bolts and a seal. A rear outlet toilet must line up with a wall connection at the correct height and position, and a wall-hung version must be secured to a rated carrier. That alignment work is more demanding.

Do rear outlet toilets save floor space?

They can reduce the gap behind the toilet and make it easier to tuck the bowl against the wall. But the bigger space gain comes from the overall bathroom layout and bowl size. For small rooms, also consider a compact model and measure clearances.

Does outlet type affect whether a toilet is WaterSense labeled?

No. WaterSense certification is based on flush volume and performance, not on where the discharge outlet is located. EPA says WaterSense labeled toilets use 1.28 gallons per flush or less and are independently certified to meet performance criteria. Choose the outlet type that fits your drain, then look for the label.

Is a rear outlet toilet the same as a wall-hung toilet?

Not exactly. A wall-hung toilet usually uses a rear discharge into a frame, but a floor-mounted toilet can also have a rear outlet. The useful question is where the drain connection is: floor or wall. For wall-hung details, see wall hung toilet buying guide.