Architects: Want to have your project featured? Showcase your work through Architizer and sign up for our inspirational newsletters.
You have to have a sense of humor when talking about toilets. There’s no getting around the fact that they aren’t the most charismatic building-product in the world, but they are very important (everyone has to use them), and they are actually pretty incredible feats of engineering.
We talked to Ilker Hussein, Commercial Director at Swiss bathroom ceramics manufacturer LAUFEN, about the precision and art that goes into designing a toilet and what architects should keep in mind when selecting one. “The science of flushing is very precise. The position and the angle of the bowl, and the bends within the design of the toilet, are really, really critical,” Hussein said. “This is why you find that customization tends to be prevalent with washbasins, baths, shower drains, etc., but not necessarily with toilets.”
Toilet crafting at LAUFEN
There’s quite a bit to learn about toilets, but we’ve helpfully broken down everything you need to know:
Siphon or Wash Down?
This distinction is a little tricky to explain because it deals with the physics of how a toilet flushes, which is something most people don’t pay much attention to. Yes, we know that water swirls in one direction in the Northern Hemisphere and the opposite way in the Southern Hemisphere, but there is also a great divide in the technology that European toilets use to flush and the technology that Americans use. American toilets are perfectly functional in Europe and vice versa, but it’s good to be aware of the tradeoffs of the two types before selecting a product.
Wash down flush mechanism; image via Fine Homebuilding
Americans typically use and produce siphon flushing toilets. Siphon toilets use a pretty ingenious system of water and air in the trapway (the pipe that carries waste out of the bowl) connected to the toilet’s tank to suck waste out of the bowl.
Wash down flush mechanism; image via LAUFEN
Europeans use and produce wash down toilets, which essentially just let water falling from the tank push water and waste out of the bowl. Wash down toilets have the dual flush option, which controls how much water is released from the tank when flushing.
A comparison of siphonic and wash down trapways; image via TOILET FOUND!
Neither system is objectively better, and both have tradeoffs. Siphon toilets rely on narrow trapways in order to generate sufficient suction, which means they are more prone to clogging, but the high water level in a siphon toilet bowl is better at hiding odors and bowl marks created by waste. They also often stick out farther from the wall in order to make room for the convoluted trapway they require. Wash down toilets don’t physically need very much water to rest in their bowls, but that means that waste often just sits exposed while the toilet is being used.
Wall-Mounted or Floor-Mounted?
Here is another European-American divide. Europeans are more used to wall-mounted toilets that stick out from the wall, and Americans are more used to floor-mounted toilets that sit on a footing, although that is changing. “When people talk about contemporary bathrooms, they tend to categorize contemporary bathrooms as having a wall-hung toilet,” Hussein said.
A wall-mounted toilet from TOTO showing the in-wall components; via TOTO
Wall-mounted toilets are easier to clean around — mops can run right under them, and there’s no tight cavity between a tank and the wall — but they usually require that the tank is built into the wall. “The biggest benefit to having a floor-mounted toilet is that you don’t need to have a hidden cistern. To have a wall-hung toilet, you will need a pan behind the wall, so you would have to create a duct or a false wall,” Hussein said. This means that the wall behind the toilet has to be built out or in some way make space for the large tank. Typically, wall-mounted toilets are more expected in high-end projects around the world.
One-Piece or Two-Piece?
Standing toilets can either come as a single unit that includes both the bowl and the tank, or they can be bought as two separate units. Two-piece toilets are more traditional and are usually cheaper, but one-piece toilets can be easier to install and clean.
Shower Toilet?
A shower toilet is not actually a toilet in the shower, as some of the more fantastical of us may have originally thought, but is a toilet that combines that bidet and spray nozzle functionality that many people associate with the Japanese toilet manufacturer TOTO, although they are now available from global manufacturers. Hussein told us that these toilets were actually first developed in Switzerland but that a Japanese toilet designer took the concept to Japan, where he pioneered it and marketed it to the receptive local market. These toilets are becoming more common around the world, but in many places, they are still considered eccentric luxury items.
The Riva toilet from LAUFEN
With the big questions out of the way, let’s move on to the more stylistic points of toilet design:
Toilet Bowl Shape: Did anyone else know that there were different classes of toilet bowl shapes? As Hussein pointed out, it’s far from a trivial design issue. The exact shape of the interior of the toilet bowl is critical to facilitating an efficient and powerful flush.
- Elongated: Elongated toilet bowls stick out farther than they are wide and are generally more ergonomically comfortable.
- Compact Elongated: Compact elongated toilet bowls have the bowl shape of an elongated toilet on the footprint of a round bowl.
- Round: Round toilet bowls are more traditional. They tend to be less comfortable but take up less space.
Seat Height
- Standard-Height Toilets: Standard seat heights are usually less than 17 inches.
- Chair-Height Toilets: Chair-height toilets are taller than standard, usually between 17 and 19 inches, and are more comfortable for people with limited mobility.
- Custom-Height Toilets: Wall-hung toilets can be installed at a variety of seat heights, usually between 15-⅜ inches to 28-½ inches.
Duravit wall-mounted toilet with wall flush
Flush Handle Location
- Right or left side: Usually a matter of taste.
- Top: The top button is usually a more contemporary option and is usually dual flush.
- Touchless: A very sanitary option that relies on motion sensors.
- Wall: Usually only available for wall-mounted toilets.
- Remote: Honestly, this one kind of confuses us. Maybe it would sometimes be nice to flush the toilet from another room? Maybe? Dunno. The ‘flush’ button is usually included on a multifunctional remote for smart toilets.
Flush Choice: Toilets can offer two different flush types to conserve water when flushing liquid waste. This functionality usually manifests in two differently sized flush buttons, but lever-activated flushes can sometimes pull in two different directions.
- Single: Siphon flush toilets offer only one flush and will have only one lever or button to flush.
- Dual: Toilets may have two flush options to conserve water.
- Touchless: Wall- or toilet-mounted motion sensors can be more sanitary, especially in public projects.
Trapway: Trapways, the pipes that take waste out of a toilet bowl, are visible in floor-mounted toilets unless covered or concealed.
- Exposed: Exposing the S-shaped curve of siphon-flushing toilets means that dirt and dust can easily accumulate on the pipe’s exterior. It’s a hard-to-clean option, and the bolt caps that cover the connections from the toilet to the floor may be unsightly, but it’s generally cheapest and leanest.
- Concealed: The trapway can also be covered and hidden.
- Skirted: A skirt can also cover the trapway, which gives the most streamlined and easy-to-clean option but also makes for a bulky toilet.
Smart: Smart toilets with bidet and heated seat options are entering the market, particularly at the higher end. These are still more common in Japan and from Japanese manufacturers like TOTO, but American and European brands are jumping on this, too.
Rough-In Dimension: The distance from the wall to the drain is the rough-in dimension. The most typical is 12 inches, but your wall trim size and other floor and wall conditions may necessitate a smaller or larger dimension.
Water-Saving: Before water-saving regulations took effect in Europe and the U.S. several years ago, many toilets used over three gallons per flush. Now most toilets are down to 1.6 gallons for a full flush and less for a partial flush. Toilets that use even less could be described as water-saving. The downside of using less water is that these toilets are often less efficient at getting solid waste down the trapway. Multiple flushes may sometimes be required.
Seats: Contemporary toilets come with a range of added bells and whistles on the seat, including heaters and lights. Two-part standing toilets are also often delivered without an attached seat, which means that a seat must be separately specified. When separately specifying a seat, pay attention to the bowl shape (described above).
- Bidet: Bidet seats can be attached to a conventional toilet to approximate the effect of a bidet or shower toilet.
- Lighted: Lighted seats may seem like a strange novelty, but they can actually help people with limited visibility find their way around a bathroom at night.
- Antimicrobial
- Scent-Releasing
Urinals
-
-
- Trough: The most inexpensive option, trough urinals generally don’t provide much privacy for their users. They are usually wall-mounted.
- Bucket: The most common variety, bucket urinals are manufactured in all manner of shapes, styles and sizes. They are usually wall-mounted.
- Wall Urinal: These large urinals cover the lower portion of a wall and culminate in a drain at or below floor level. They come in a variety of designs and are generally floor-mounted.
-
Duravit wall-hung toilet and bidet
Bidets
- Traditional: The traditional ceramic-basin bidet can either be wall- or floor-mounted and generally takes up the same amount of space as a modern toilet.
- Toilet Seat Bidet: A more modern take on the bidet, this product is either part of the toilet or attached to the toilet seat and cover, taking up little room.
- Hand Bidet (Shattaf): A small hose and spray nozzle connected to the toilet’s water supply.
Application
- Project Type: Is this a commercial, residential, institutional or public project? Certain building codes might dictate the size, appearance, material and accessibility of the product.
- Use: How many people are expected to use the product on a daily basis?
Aesthetic
- Materials: Toilets, urinals and bidets are most commonly made of porcelain vitreous china but can be made of other impervious material such as stainless steel.
- Colors: Toilets, bidets and urinals are most commonly variations of white, but they can be specially ordered to come in any color.
Architects: Want to have your project featured? Showcase your work through Architizer and sign up for our inspirational newsletters.