We have been sitting on the same kind of toilet for centuries. Sure, some changes have been made to the design, but as far as the actual toilet is concerned, hundreds of years have passed, and they are still largely porcelain.
However, unlike in the past, when toilets were made using regular porcelain, you will find that the porcelain used to make toilets nowadays has a glass-like shine. So what is responsible for this glass-like shine? Here’s what you might want to know about what toilets are made of.
Related: How Long Do Toilets Last?
A Brief History of Toilets
Before we dive into what modern toilets are made of, let’s take a brief look into the history of toilets. Toilets can be traced as far back as Ancient Rome. During these times, people went to public baths not just to get clean but also to do their business on stone benches.
These are some of the earliest public toilets. Over time, squat loos, which were basically holes in the floor, were introduced. These were installed in a room called the garderobe, which was often separate from the main living space.
These quickly became a favorite among the wealthy. Unfortunately, as you might imagine, such structures caused a stink. This smelly vulnerability could also be easily exploited for castle invasions and sieges.
Not a lot of people know about the history of flushable toilets and that they have been in existence since 1592. However, these took up to seven and a half gallons of water to flush. This is a lot compared to today, where you only need 1.6 gallons.
Because of how much water was required, flushable toilets didn’t become very popular until 1775. This was when the s-curved pipe was invented by Alexander Cummings. This pipe was the solution that prevented sewage gases from rising.
It was only later in the century that the ballock was invented by Thomas Crapper. This is the component that revolutionized flush toilets, and it’s why the idiom “going to the crapper” is around today.
What are Toilets Made Of?
According to Explain That Stuff!, people have been using ceramics for almost 30,000 years. Glazing, on the other hand, has only been around for around 8,000 years. Toilets are made using porcelain known as vitreous china. Vitreous china is the shiny glazing technique that makes sinks, toilets, and tubs highly durable.
Vitreous china is a mixture of several clays. It contains china clay, ball clay, silica, and a fluxing agent. These clays are hardened using air and then baked in an extremely hot oven known as a kiln. After the first firing, a shiny, waterproof coating known as a glaze is applied.
Once the coating is applied, the clay is fired a second time. What makes vitreous china special is that the glaze and the clay can be fired together. As a result, the entire body of the clay vitrifies. This just means it turns into a glassy appearance, which makes toilets waterproof and stainproof.
Toilets usually come in a natural off-white color due to the heat used. In the past, you could also find them in various fashionable colors, mainly for décor reasons. However, this trend ended in the 1970s. Nowadays, no less than 95% of toilets are white. This is for simple hygiene reasons. With a white toilet, there is literally nowhere for filth to hide.
Benefits of Vitreous Enamel Coating
When it comes to pricing, Vitreous china and porcelain are quite similar. However, the two materials have very different properties. Vitreous china is created in a way that makes it perfect for toilets. It has a coating that makes it better at resisting spills, imperfections, and scratches. Apart from that, the high-gloss enamel is highly sanitary, durable, and stain resistant.
The Toilet Bowl and Tank
The toilet tank and bowl are made using pottery. Potteries receive large amounts of liquid vitreous china, also known as slurry slip. This slurry slip is first thinned to a watery consistency to make the bowl and tank. It is then fed through fine screens to do away with impurities.
Once that’s done, the slip is re-thickened and pumped into tanks awaiting casting. The bowls and tanks are made using plaster of Paris mold filled with slip. These molds are 12% bigger than the desired pieces to allow for shrinkage.
Once the molds are filled with the slip, they are left to sit for about an hour. The excess slip is drained after an hour and stored for later use, and the clay is left in the mold for about four more hours to ensure the plaster of Paris absorbs all the water.
Once the clay dries to a point where it can be removed, it comes out as a semi-solid material known as greenware. Hand tools and sponges are then used to smooth the castings’ edges and create holes for the fittings and drains.
At this point, the bowls and tanks will essentially be complete. All that will be left to do is let them dry for about five or so days. From there, they are placed in a dryer for 20 hours at a temperature of 200° F (93° C). The casting comes out of the dryer with only 0.5% moisture. They are then glazed and ready for the kiln.
What About the Toilet Seats?
There are generally two types of toilet seats. The first type is a plastic toilet seat. These are made using polystyrene, which is a type of thermoplastic. The second and less expensive toilet seat, which is also more common, is made using a mixture of plastic and wood. This process uses hardwoods like birch and maple.
The wood is ground into a flour-like consistency before being blended with a powdered plastic resin known as melamine. Before being heated, a third ingredient is added to the wooden toilet mix. Zinc stearate is added to the mixture to prevent it from sticking to the mold during manufacturing.
Wooden toilet seats come with metal flank fixtures that are made of copper or stainless steel, and the joints connecting the seat to the bowl are usually made of rubber-like plastic.
The Making of Plastic Toilet Seats
Plastic seats start off as polystyrene pellets. These are fed into a hopper connected to an injection molding machine. The hopper measures a precise amount of pellets that move into a second container where they are heated until they melt.
The liquid polystyrene that results flows into a two-part mold through a small hole in the center. Molds for toilet seats are made using chrome-plated machined steel. The two halves of the mold have an open space in between that has the shape of toilet seats and covers.
Once fully loaded, the mold is closed using a huge hydraulic press that exerts 4,540 kg per square centimeter. The polystyrene is heated to 400° F (204° C) during this process. As soon as the melted plastic takes the form of the mold, the heating is stopped.
Cool water is used to bring the temperature of the mold down and speed up the solidification process. Once solid, the hydraulic clamp is released, separating the two halves of the mold. The resulting seat is then placed in a water bath.
The Making of Wooden Toilet Seats
The first step in making wooden toilet seats is mixing wood flour and plastic resin. The wooden toilet seat mixture contains 15% powdered plastic resin; the rest is wood and zinc. This mixture is passed to the attrition mill, where it’s ground into a fine powder.
Once this step is complete, the powder will proceed to the molding press, where it’s heated to 300° F (149° C). The mold will be clamped at 150 tons of force during this process. The fusion of the wood and plastic mix takes about 6.5 minutes.
After that time, the mold is opened, and the seat is taken out. From there onwards, the finishing of the wooden seats is the same as that of plastic seats. Both seats are drilled and sanded before they are painted and dried.
Why Are Toilets Porcelain?
The number one reason toilets are made of porcelain is that the material offers a lot of properties that are not found in any other material. For instance, it is super easy to clean; it’s affordable, hygienic, and comfortable to use. On the other end, regardless of how well you seal it, wood is still porous and will expand from water.
You might be thinking about why metal isn’t used as much. Well, metal is hygienic, easy to shape, and affordable. However, the major downside is that sitting will always be cold and unpleasant.
Another material that could have been a good contender is modern plastic. Unfortunately, like all the others, it also has its limitations. It’s porous and warps when repeatedly made to bear heavy weights.
Porcelain has a smooth surface, and when used for toilets, it’s paired with modern glazing techniques. This makes it super easy to clean. Having a clean toilet is critical to public health. Apart from the discovery of penicillin, the evolution of the toilet and its inclusion in the home is one of the most significant advances in public health.