#there is literally no reason to resort to “lol they relieved themselves were they stood”

[arkadijxpancakes]

Uh, historical hygiene in the wizarding world! This is fun!

First things first: Regarding the "they simply relieved themselves wherever they stood, and vanished the evidence"-thing - it's even worse than what you mentioned.

In the books, the vanishing spell (Evanesco) is taught in fifth grade. Fifth. It's supposed to be pretty advanced transfiguration magic. So even if we assume that the age required to start education at Hogwarts wasn't fixed in the past and students could enroll earlier than eleven, and if we additionally assume, that the spell was taught a little bit earlier, too ... it's still a long wait to get potty-trained. And that's, what it is, isn't it?

Just imagine school-ages children shitting everywhere and not vanishing the evidence, because they simply can't cast the required spell yet. Some might be never able to cast it reliably, because it's relatively advanced stuff and not everyone is good at transfiguration.

I doubt anyone would want to put up with something like that. Even if you send an armada of house elves after those kids ... no. And it gets worse, when you consider, that those kids spent time at home, too. Before Hogwarts, of course, and during any holidays they might've had. And while Hogwarts has lots and lots of house elves, most families probably didn't. Can you imagine a medieval Molly Weasley, constantly running after her kids, just to vanish their shit? Yeah, that's not going to happen. Those kids will use some form of toilet, whether they want to or not.

So, yeah. They really should have some form of toilets.

As for what they did instead, you've already made some great points. (And anon, did, too!) This topic is so interesting! So I want to yap about it, too - especially about what we could expect during the Middle Ages.

Regarding toilets:

At home, I would assume that most families used a combination of chamber pots and outhouses and just clean those with magic. (Or forced their house elf to do it.)

Humans have used outhouses for ages. Some of our best archaeological sites were originally some form of outhouse. It would be really strange if medieval wizards hadn't used them too.

When it comes to Hogwarts, I agree that they would've used a combination of chamber pots and other forms of toilets.

My guess is: Every student had their own chamber pot in their dorm. In the common rooms, students would simply go to their dorm and use their pot. They would either clean those themselves or the house elves would do it for them.

Toilets outside the common room are a little bit tricker to define. It probably depended on location. For everything that is on or near the ground level, they could simply use outhouses.

On higher floors, they could've used garderobes. Back then, garderobes (at least the toilet-version) were usually located in small chambers on the outside wall of a castle. They would have a seat made of stone or wood with a hole in the middle. The waste fell through the hole, usually into a cesspit or the moat. It's likely, that Hogwarts had something similar, in a couple of different locations. (Probably on the side that faced the lake. Please don't dwell on that.)

When it comes to baths:

I don't think that they used the prefect bathroom. That thing is probably pretty new, too.

However, I do think that they did use some form of bathhouse. Bathhouses were really popular, during the Middle Ages. Like, really fucking popular. So, it's likely that Hogwarts had at least one.

That said, it probably wasn't like a Roman bathhouse and probably had no pool. It also wasn't really a luxury either. (I mean, they could be, of course. But the "basic" version was pretty affordable and most city dwellers used them regularly, especially during the late Middle Ages.)

Instead of a pool, the bathhouse had probably the following things:

Basins with warm water, that a student could use to wash themselves

a couple of tubs (probably made of wood) for bathing

at least one steam bath (kind of like a sauna)

additional services, probably performed by either a house elf or by a witch or wizard (mostly washing and cutting of hair and shavings for older students and teachers)

So imagine something that looks more like this:

or this:

(Note: The second picture is a medieval illustration of the Facta et dicta memorabilia, written by Valerius Maximus, a Roman author who lived in the first century. So the scene depicted isn't medieval but Roman. However, the style of the bathhouse (the wooden tubs and the clothing) is medieval.)

Okay, back to Hogwarts.

I assume that Hogwarts had one, big bathhouse that was used by everyone (teachers and students alike). It was probably located somewhere near the lake, to make transportation of water (especially waste water) easier. It's also possible, that each house had its own bathhouse, but that would make removing waste water a little bit more difficult. (Unless this, too, could be vanished.)

In addition to that, students and teachers probably had a bathing routine.

In the morning, everyone would wash themselves in their dorm/sleeping quarters. For this, they would use a small basin with (warm or cold) water and a small cloth. Hair would only be brushed. Long hair would be brushed. Most people would probably wear their hair braided or in an updo and covered by their hat.

In addition to that, everyone would use the bath house. Because of the number of people living in Hogwarts, there was probably a schedule in place, that dictated who was allowed to use the bathhouse at what times. Gender separation is possible, but not necessary. If it did happen, it was either done by providing separate facilities or simply by allotting time slots.

It's possible, that each house had its own bathing day. Either that, or baths were scheduled on Saturdays and before important holidays. Students and teachers would also use the bathhouse to get a haircut or a shave. And maybe some cupping therapy, if they were into that kind of thing.

Some celebrations might've also happened there. (I could imagine some quidditch teams celebrating their victory with a nice, hot steam bath, for example.)

Apart from that, students would probably also wash themselves in the lake. At least during the summer, when temperatures were warm enough.

Do you think Hogwarts has baths for all students? It’s something I’ve been thinking about, since I can’t remember if the bathing situation of students is mentioned outside of the prefect’s bathroom and the huge tub.

I’ve always kind of assumed modern students use showers, but I don’t know for sure - and now it dents me on a spiral of ‘wait, do they just use smaller tubs?’

As far as I can tell, modern showers were first patented somewhere in the the late 1760’s. Which means that if there are showers, they would have been added during later renovations - like the bathroom entrance to the chamber of secrets.

So, pre-renovation, Hogwarts students would probably sponge bathe with basins of water or, later in the Victorian era or early Edwardian, move onto full bathtubs.

(Also, and this is more of a nitpick on my part, what was with the statement that wizards and witches would just vanish their waste? Chamber pots and commode chairs still existed at that time???)

Okay, so this is an interesting one. So, plumbing that would allow water to reach all sections of the castle, particularly the high towers (Gryffindor & Ravenclaw), yeah, that's not happening in the early days of the school. Or even when the shower was invented. Water taps for indoor plumbing that allowed to get water in and not just get the waste out was a late Victorian invention.

As per usual, I went a little overboard with research, so it's under the cut.

According to the old Pottermore article on the matter:

When first created, the Chamber was accessed through a concealed trapdoor and a series of magical tunnels. However, when Hogwarts’ plumbing became more elaborate in the eighteenth century (this was a rare instance of wizards copying Muggles, because hitherto they simply relieved themselves wherever they stood, and vanished the evidence), the entrance to the Chamber was threatened, being located on the site of a proposed bathroom. The presence in school at the time of a student called Corvinus Gaunt – direct descendant of Slytherin, and antecedent of Tom Riddle – explains how the simple trapdoor was secretly protected, so that those who knew how could still access the entrance to the Chamber even after newfangled plumbing had been placed on top of it.

(Pottermore)

Proper, elaborate plumbing only made its way into the school in the 18th century but this plumbing would only be to be rid of waste, not get water into taps.

(The above quote is also the source of the wizards vanishing their waste, and you're right that it's really weird. I assume they still wanted privacy when doing their business. Like, I can see them still having privies and chamber pots but instead of throwing the waste somewhere, they vanished it. Like, I just can't imagine someone peeing/shitting in their robes in public willingly, I'm sorry, that is not realistic. People didn't do that, yes there were public toilets where other people could see you shit, but it's a space specialized for it (you're polite and don't look, like with urinals), it's not like anyone shat at the dinner table. Like what? What does she mean by "wherever they stood"? I refuse to believe they didn't go somewhere secluded-ish/specialized before going about their business and then vanishing it)

Cedric advises Harry to take a bath with the egg:

“What?” “Take a bath, and — er — take the egg with you, and — er — just mull things over in the hot water. It’ll help you think. ... Trust me.”

(GoF)

Which leads me to assume all students have baths and not showers in their dorms (or wherever they have them). This is supported by later quotes I found:

“Yes, it was,” said Ginny. “It was appalling. Angelina was nearly in tears by the end of it.” Ron and Ginny went off for baths after dinner; Harry and Hermione returned to the busy Gryffindor common room and their usual pile of homework.

(OotP)

Ron and Ginny go to take baths after Quidditch practice (Harry was already banned) and I don't believe they are using the prefects' bathroom. What I note here as interesting is that Harry and Hermione return to the common room while Ron and Ginny go to the baths separately. Why are the baths implied to not be in Gryffindor Tower?

But in PoA, there are also showers, which I assume are in the Quidditch changing rooms:

“Where is Wood?” said Harry, suddenly realizing he wasn’t there. “Still in the showers,” said Fred. “We think he’s trying to drown himself.”

(PoA)

So, what I think is that by the time the books take place, the dorms have baths (the phrasing in the OotP quote is weird, but I'm pretty sure the baths are in the dorms/common rooms) and the Quidditch changing rooms that are not part of the castle and easier to renovate have showers.

(The other option is that they have cool covered Victorian baths that also functioned as showers and they also look really cool:

The above enclosure has a shower head inside. So, maybe, though less likely with how the quotes are phrased)

Now, baths have been a thing for a long time, but until the late 19th century, basically no one had indoor baths like we do today or pipes that got water into homes. There were pipes that supplied water to London, but you had to go to specific stations and get buckets of water to then heat and pour it into the bath at home. The bath day was a whole ritual.

The first screw-down water tap was patented in 1845, so the plumbing Corvinus introduced would've been just to dispose of sewage and waste and not taps for baths like I said earlier. Plumbing that supplied water to individual houses was only introduced in the late 19th century for the wealthy and early 20th century to the rest, so Hogwarts wouldn't have seen it until then.

Since Hogwarts has an army of house elves running it, it's very possible they ensured the baths always had clean warm water for students. Additionally, older students could just cast Aguamenti to fill their baths with clean water, so I don't think taps were all that important to them. So, I think the dorms having a bathroom (I assume one for boys and one for girls) that you had to fill in yourself with magic or call an elf to help (for younger students) isn't too far-fetched. That along with a washcloth, bowl, and pitcher to wash their face in the dorm room would've likely covered the hygiene needs for the most part. And again, baths have existed for thousands of years as there are accounts of very old public bathhouses, so it's likely they would've been a thing in Hogwarts even before modern plumbing was introduced (as they were in the muggle world). But I don't think the "private-ish" baths in the dorms were always there.

Which leads me to prefects' bath:

About a hundred golden taps stood all around the pool’s edges, each with a differently colored jewel set into its handle. There was also a diving board. Long white linen curtains hung at the windows; a large pile of fluffy white towels sat in a corner, [...] at the side of the swimming-pool-sized bath, then knelt down and turned on a few of the taps. He could tell at once that they carried different sorts of bubble bath mixed with the water, though it wasn’t bubble bath as Harry had ever experienced it. One tap gushed pink and blue bubbles the size of footballs; another poured ice-white foam so thick that Harry thought it would have supported his weight if he’d cared to test it; a third sent heavily perfumed purple clouds hovering over the surface of the water.

(GoF)

The prefects' bath is described very similar to a public bathhouse. Roman bathhouses and some medieval ones occasionally had these huge pool-like baths that everyone would use together.

These bathhouses were a luxury though, you wouldn't have gone there every day. It was an event, you'd talk to people, you'd eat, it was a whole thing. So it was more a social thing than just cleaning yourself, you had a washcloth at home for that.

So, my headcanon is that when Hogwarts was built, all students used the prefects' bath as that was the student's bathhouse that everyone used. Later in the Middle Ages, the dorms got more private baths:

(Though people often still used these above baths together and even sat to eat there, since, again, heating up all the water for it made it a luxury. Wizards though, would probably bath more often than muggles since they have magic that can fill the baths and heat them for them)

These more private baths would probably be when the aforementioned bathrooms (still semi-public for a whole house) would be introduced. Later when one-person baths became the norm they would be switched out to these:

these baths would've still had to be filled manually via spells or by the house elves. Modern baths with taps are a 19th-century invention and didn't become common until the early 20th century. In the Victorian era, you just needed to wash your face, feet, genitalia, and armpits every day, a full proper bath was still not an everyday occurrence for most of that century.

The late Victorian era came with the introduction of taps in baths and dedicated bathrooms (or "water closets") more similar to what we are familiar with today:

(Center drain, wood rimmed enameled cast iron tub with ornate feet, embossed skirt, marbled with figural tiled facade, Standard Manufacturing 1887)

These bathrooms were reserved only for the wealthy (since plumbing was expensive) who usually transformed an unused bedroom into a bathroom. These rooms were kind of embarrassing for people to see due to their private nature (hence why the baths and toilets were often rimmed or surrounded with wood to make them look like regular furniture. There were even "folding baths" so you could hide the bath when not in use)

In the very late 19th century tubs started to be made fully from copper or cast iron and these baths would become a common household appliance in the early 20th century.

(Roman pedestal Tub, Standard Manufacturing 1914)

Also, The early showers of the 18th century had a water pump that could spray water from above:

But it still had to be manually filled with water and was not common in homes until the latter half of the 20th century, which is when they would be introduced in the Quidditch changing rooms, but not inside the castle. (Yes, there were some late Victorian shower-bath hybrids and even just showers for homes, but they weren't very common from what I've read)

So, this is what I have to say about the baths/shower situation at Hogwarts.