Selecting Bathroom Fixtures Choosing The Perfect Toilet

The can, the throne, the head, the john, the privy, the WC, the crapper, the lav, the loo, the potty, the commode, the oval office — whatever your favorite euphemism, what you mean is, plain and simply, the toilet.

The flushing siphon toilet was the invention that moved the bathroom indoors. To many architectural historians, it is the single most important household innovation of all time.

Modern toilets consist of a bowl fitted with a hinged seat and a tank that holds water for flushing. The bowl connects to a drain pipe through which waste is flushed into a sanitary sewer. The design has worked well for over a century and a half.

By preventing diseases like dysentery, cholera, and typhoid — about 50 diseases in total transmitted through contact with human waste — the toilet and modern sewer systems have saved countless millions of lives and made modern cities possible.

The first (English) patent for the modern flushing siphon toilet was issued to Alexander Cummings, a London watchmaker, in 1775. Cummings used a drain pipe with an "S" curve that trapped water, creating a seal that prevented the escape of foul gases rising out of the sewer. It made the indoor toilet practical.

An enterprising London plumber, Thomas Crapper, however, made it affordable.

Crapper is wrongly credited by many Americans as the inventor of the flushing toilet. He did not.

He started a decorative fixture company, Thos. Crapper & Co., Ltd., in England in 1861. The company is still in business. Its showroom, the first of its kind, sold toilets, baths, and sinks on King's Road, London until 1968 when it moved to its present location on Ashbrow Road in Huddersfield.

Crapper toilets featured an advanced siphon design invented in 1898 by one of his employees, Albert Giblin. After the invention of porcelain enamel toilets by London pottery maker, Thomas Twyford in 1870, Crapper and Twyford teamed to manufacture and sell the products.

The porcelain enamel toilets were enormously popular and such a huge improvement over earlier wood, copper, and iron models that other toilets were driven from the marketplace.

By the 1850s most new homes in London included a "water closet" that drained into the city's new sanitary sewer.

By 1917 the Crapper name was emblazoned on so many toilets that American soldiers and Marines passing through Britain on their way to the Western Front during the First World War wrongly concluded that "crapper" was the official name of the device.

The plain but functional toilets sold to England's emerging middle class were given are artistic twist by fine porcelain makers such as Wedgewood and Royal Doulton for sale to the well-to-do.

The Wedgewood and Doulton names were imprinted conspicuously on the highly decorated toilets they manufactured, and a great many of these are still in use in the U.K.

(For more information on the evolution of the bathroom in Victorian times, see The Victorian Bath.)

Toilet Con­fig­ur­a­tions

There are two basic types of toilets in use in North America and Europe: one-piece and two-piece.

Two-piece toilets

Two-piece toilets have a separate tank and bowl bolted together. The original siphon flush toilet had a separate tank and bowl. The tank hung high on the wall to provide enough flushing force.

With better mechanisms, the tank was able to sit right on the bowl, and this is still the most widely used toilet type and a good choice for most applications.

One-piece toilets

One-piece toilets were introduced during the 1930s.

These low-profile models can be installed beneath wall cabinets or a storage shelf, places where the taller two-piece models will not fit.

Since it is an integrated unit, there is no space between the tank and bowl of a one-piece unit where a leak can occur or unsanitary liquids can collect, so this type of toilet is easier to keep clean.

Toilet Mounting

Most residential toilets sit on the floor. Most commercial toilets hang on the wall. Why wall mount? It makes cleaning "behind" the toilet easier because there is no "behind" to clean.

Wall-mount toilets for home use are available and recommended where possible because they do make cleaning easier and are, therefore, much more sanitary.

They are more expensive to buy and more expensive to install. Expect to pay at least double for a wall-mount toilet, and at least double for the installation. This may sound like a lot, but in the context of a bathroom remodel is about an additional 6%.

In exchange, you get years of convenience. Once you've installed a wall-mount toilet you will wonder how you ever got along without one.

In the latest variation on the wall-mount toilet, the tank and flushing mechanism are hidden in the wall, accessible through a removable panel that also holds the flushing control — usually a button. Only the toilet bowl and seat are visible.

Few manufacturers offer them, but the list is growing. They are even more expensive to buy and more expensive to install than wall-mount toilets. Nor are they suitable for every bath or every bathroom remodel. But, if you are going to open up the wall anyway, they are worth considering. In-wall toilets take up very little room, so for very small bathrooms, they are one additional solution to the space problem.

Toilet Offset

For floor-mounted toilets, the offset is important. The offset or setback is the distance between the wall behind the toilet and the center of the toilet flange. The flange is the pipe segment the toilet sits on. The standard offset is 12". Unless you specify otherwise, this is the offset you will get.

Many older one-piece elongated toilets required a 14", 16" or even an 18" offset. Today that has been largely standardized to 12", but if you are replacing an old toilet that needed a 14" or 16" offset, you may have to move the flange, or use an offset flange, which can, under certain circumstances, allow a 12" offset toilet to be used with 14" offset plumbing.


One of the most welcome innovations in toilets in recent years is the high-rise seat. Termed "comfort height" or "right-height" toilets, the extra height makes it easier for people with movement issues to use.

When combined with well-placed grab bars and transfer benches, these raised toilets improve the quality of life for the elderly and movement impaired.

The Americans with Disabilities Act (ADA) requires accessible toilets to have a seat height of between 16 1/2" and 18", compared to the normal 14" to 16" for standard rise toilets. Since you are not getting any younger, plan ahead and make your next toilet an accessible unit.

Also, pay attention to other accessibility issues. Toilets need to be placed so there is enough room to use the toilet without interference from other fixtures or other people using the bathroom.

The Rules of Good Bathroom Design offer very clear guidelines on where and how to install a toilet and the amount of front and side clearance required. Front clearance, in particular, may determine whether you have space for an elongated toilet bowl.

Side clearance is usually dictated by your local plumbing code, which usually requires 15" from the centerline of the toilet to any wall or cabinet to the side of the toilet.

This is a step up from the 1950s which often required just 12". So if you are replacing a toilet in a small bath that has just this 12" of clearance, you can only hope you are grandfathered and can stick with the 12" clearance.

Usually, you will be, but, check with your local code authority to be sure.

The minimum side clearance used by most bath designers is 18", which is the Design Guidelines minimum.

Flushing Mechanics

Until January 1, 1994, residential toilets could use up to 5 gallons of water per flush.

After that date, in response to water shortages and municipal sewer system problems, the Energy Policy and Conservation Act limited new toilets to no more than 1.6 gallons of water per flush.

That was a large and abrupt change and it initially caused problems. Early low-flow toilets did not work well. It took a while for the industry to get a handle on the new technologies required. Newer low-flow toilets, called "High-Efficiency Toilets" or HETs, are a vast improvement on earlier designs.

The newest round of water-saving legislation, already mandated in many states, will allow no more than 1.2 to 1.4 gallons per flush.

To improve the performance of low-flow toilets, engineers developed flushing mechanisms that do not rely just on gravity and siphon action to remove waste. Some use high-pressure bladders, and others electrical flushing mechanisms. None of these have, however, made much of a dent in the residential toilet market, and the gravity-fed siphon toilet is still very much the king of the flush.

Siphon Vacuum Flushing

Most low-flow toilets use gravity-fed mechanisms. This is the traditional way toilets have worked since the siphon mechanism was invented. Press down the lever, and water is released from the tank into the bowl. The weight and force of the water moving over the trapway creates a vacuum that causes a siphon action that "flushes" the toilet.

The newest wrinkle in low-flow siphon technology is the dual flush system, a very low flow flush for liquids, and a higher flow for solids.

Pressure Assisted Flushing

In pressure-assisted systems, water enters the tank under normal household pressure, compressing an air bladder inside the tank. When the flush lever is pushed, the pressurized water surges through a jet and expels waste with more than gravity force. The flushing action is noisier, but refilling is quieter, and there's no condensation or "sweating" on the outer tank.

Invented to overcome problems with early low-flow siphon toilets, adherents continue to promote pressure-assisted systems as being water-saving, which they are. They require less water to produce the same "carry" – the amount of waste that can be flushed.

Some companies offer a pressure-assisted mechanism designed to fit into conventional siphon toilets. The best-known is probably Flushmate. The company claims that the mechanism converts a normal toilet into a flushing behemoth with a carry equivalent to using 70 gallons per flush, while actually using less than one gallon of water.

Pressure-assisted systems have their own problems, however. They do not work well with low water pressure and the lifespan of the bladder is typically only 5 years. If they fail you are out of luck until the problem is fixed. By contrast, a siphon vacuum toilet is very unlikely to stop functioning altogether, even if you have to feed it with a bucket of water to make it work.

Powered Toilet

Kohler Power Lite® "toughless" panel-pperated electric toilet washes and air-dries the user after sit-down use, eliminating the need for toilet paper, as well as creating a powerful fush with little water use. The drawbacks: The toilet will not operate in an electrical failure, and costs arount $3,000.

Powered Flushing Mechanisms

A powered flushing mechanism uses a small electric pump to push water and waste through the toilet. These toilets were invented for boats, and are less frequently used in houses. They fell out of favor for most of a decade as sophon toilets became more efficient and the need for powered systems decreased.

They are now in midst of a revival. Electric power is used not just to flush the toilet but to operate an integrated bidet which eliminates the need for toilet paper. Kohler, for example, has a model that includes a washer, air dryer, illuminated bowl, and hands-free operation.

The toilets require a connection to household current which often makes them unsuitable for retrofitting in an existing bathroom. They will not work if a power loss occurs, which could be, to say the least, awkward. Some models have a siphon backup, just in case.

How to Select a Toilet

Know the Offset: Don't assume your toilet offset is the standard 12". Many are not. Get out your tape measure and make sure. If it's not 12" call a plumber for advice. An off-standard offset is usually not something you will want to deal with.

Bowl Length: An elongated bowl front makes a better urinal and is more sanitary. It will give you about 2 inches of extra length and support. The trade-off is that it takes more floor space in a small bathroom. Round bowls have a shorter front-to-back dimension, making them a better choice for small or narrow spaces. Seats are generally not included when you buy a new toilet, so be sure the seat you buy matches the shape you need.

Seat Height: Both round and elongated styles are now being made with seats up to 18" high — 2 to 3 inches higher than standard.

This height is more comfortable for many people because they don't need to bend their knees as much to make use of the toilet, and should be a strong consideration if any user has or anticipates physical problems with knees, hips or back.

Footprint & Wallprint: If you are replacing an existing toilet that has a large footprint (i.e., the base covers a large floor area), consider the patching and repair to the floor that might be required if a bowl with a smaller footprint is chosen.

This is especially an issue where ceramic tile covers the floor around the toilet. Will additional matching tile be required and will the appearance be satisfactory? Footprint dimensions of most new toilets may be found on the manufacturers' websites.

If you are replacing an existing toilet with one that has a larger footprint, consider whether there will be enough clearance to adjacent walls or fixtures.

Most plumbing codes specify a minimum clearance of 21" in front of the toilet (30" is recommended) and at least 15" from the centerline of the toilet to any obstacle or either side (18" is recommended). See the Illustrated Rules of Good Bathroom Design for more information.

If you are replacing an older, low-efficiency toilet with a new high-efficiency toilet, the tank on the new toilet is likely to be smaller — much smaller in some cases.

If the wall hidden behind the old tank is unpainted (or untiled, as the case may be), which is not at all uncommon, the smaller tank may leave the unfinished wall visible.

There is no cure for this except to paint the exposed area before you install the new toilet. The old large tank toilets are no longer available, and if available, would be illegal to install.

Shut-Off Valve and Supply Hose: Water is supplied to the toilet through the supply hose connecting a shut-off valve (or "angle-stop") to your toilet tank. Check the condition of the valve by turning it off to see if the water is indeed shut off.

If the hose is frayed or worn, you probably need a new one. Consider one encased in a stainless steel mesh-type hose for long-term durability. If the shut-off valve needs replacing, all of the water in your house will have to be turned off temporarily, often a job better suited to your plumber.

Tank Condensation: If you live in a high-humidity area, you may experience problems with water condensation on the outside of your toilet tank.

This was more often a problem with older, large tanks that emptied completely when flushed. Newer tanks empty just partway, so the colder water refilling the tank is less likely to cause condensation.

But, if you have the problem, there are insulated toilet tanks designed to cure it, and pressure-assisted flush mechanisms usually hold the water in a plastic container inside the tank, not in the tank itself, so these also get rid of condensation.

Flushing Efficiency:  You should always check the latest MaP testing results. Surprisingly, high-performance toilets are not necessarily prohibitively expensive. In fact, some high-rated toilets are priced very competitively with their low-rated cousins.

Do not be awed by toilets that can flush a potato or 20 golf balls at a time. These are not real-world tests (unless you intend to dispose of your potatoes or golf balls in this highly unusual manner).

Look for the MaP Test results. The MaP score should be at least 600, higher is better. If there is no MaP score, pass it by. You don't want a toilet the performance of which is unknown. To find out more about MaP, see MaP Testing sidebar, above.

Showers and Bathtubs

There are three basic types of showers: showers built over separate tubs, integrated one-piece tub-shower units, and stand-alone showers. All these types are prefabricated by a number of manufacturers, and all can be custom-built by a qualified local craftsman… (Continues)

Rev. 09/30/23