When designing a building, you have to account for things like terrain, materials, weather, handicapped accessibility and, of course, ghosts.
You can design a building more awesome than the Guggenheim and nobody will want to go in it if there's evil spirits just running through it willy-nilly. With that in mind, here's how people in different parts of the world build guaranteed demon-free housing.
Quick, what do you think of when I say, "Chinese architecture"? The first thing you probably think of is that the doorways don't need to be as high, and then the second thing is probably those weird curvy roofs like you always see on pagodas.
Why do they build them that way? Because of ghosts. Did you know that spirits can only travel in straight lines? Well, according to Chinese tradition, anyway. Sure, they might be evil spirits, but they're Chinese evil spirits, dammit, and they are going to do things by the book. None of this individualistic zigzagging and newfangled "turning." No sirree, we're just going in traditional straight lines like we've been doing for thousands of years, thank you very much.
They're also afraid of fireworks. Goddamn, do we have the stupidest evil spirits ever.
That's the explanation given for many curvy roads and paths in China, and the fact that it's easier to curve the roads to follow the contours of hilly terrain is probably just a coincidence.
This is an actual military road in China. I'm sure it's completely ghost free.
And that's why Chinese roofs are curved, supposedly. I'm not sure what happens when the straight-line spirits hit the curvy roof but I like to think they slide along the curve and fly right off the end, and also that they go, "Wheeeeeeeeeee!" while doing it.
If you've ever been shopping for house paint, you know there are a lot of ridiculous names out there for blue, leaving you confused whether you want "Utah sky," "blue lapis" or "windmill wings." Haint blue is sort of the opposite. It's one name for a whole bunch of shades of blue -- the exact shade doesn't matter as long as it repels ghosts, or "haints."
Does not repel poor maintenance.
As everybody knows, ghosts can't cross water, at least according to the Gullah people of the American South. The Gullah, descendants of African slaves, did not have money to mix standard paints at the Home Depot so they made their own paint -- mixing lime, milk and pigments in pits to make a blue paint that looked like water, which, when applied to a house, would obviously convince ghosts that the house was covered with rivers or something. They would paint porch ceilings as well as door and window frames. You know, all the typical ghost entry points.
Another story purporting to explain the porch ceilings specifically says that they're actually painted to look like sky, causing the spirits to think they're the way up to heaven. So they walk right on up to your porch, intending to give you a good haunting, moaning and complaining about how they're trapped between this world and the next, and then look up and go, "Oh, hey, heaven!" and make a quick 90-degree turn upward before they reach your door.
I guess they're too dumb to figure out what happened, or else that would be a recipe for some really mad haints coming back to your house in a bit.
And another theory is that some people were just embarrassed about looking so superstitious so they painted the porch ceilings where people couldn't see them from the street. The important thing, after all, was that the ghosts would see it when they got there.
If you don't have your own backyard paint-mixing pit, you can buy actual Benjamin Moore-based haint blue shades today, if you trust mass-produced corporate formulas when it comes to protecting your home from ghosts.
I don't know whether Japan's spirits are like the Chinese ones and thus can't navigate corners or whatever, but I can tell you they all come from the same direction -- the northeast, or "kimon." Kimon means "demon gate," and is where the bad spirits come from. As you can guess, that would be a bad place to put a door.
The view would be terrible.
It would be a good place, obviously, to put something like a guard tower. Hiji Castle, for example, has a kimon tower on the northeast side, to guard against evil spirits. They even cut off the kimon (northeast) corner of the kimon (northeast) tower to be extra safe, somehow.
I guess that's kind of smart, actually. Structurally, a corner is a weak point. Flattening it off means it can stand up to more damage from demons before it begins to break down. I have no idea what kind of calculations you'd do on a structure to measure how much spiritual damage it can withstand, but you know what? I'm not an ancient Japanese architect. I'm not going to tell them how to do their job.
Say you're an average Japanese person. You live in an apartment. You can't build a fucking tower. How are you going to ward off spirits to protect your home, your family/robot companion and your spouse/pillow with a picture of an anime girl on it? Well, I guess your landlord is responsible for making the building kimon-safe on the outside, and the only way the spirits will get into your apartment is through your plumbing, so that's why it's a pretty big deal to not build a bathroom in the kimon corner of your apartment. I guess this is something quite a few Japanese people still actually care about.
Because nobody wants ghosts in their apartment to begin with, but if anything could make that worse, it's probably a ghost crawling into your apartment covered with an entire apartment building's worth of sewage.